OPINION
JONES, Chief Justice.Jacob L. Miller died on November 3, 1971, leaving an original will, with various codicils thereto, containing many interlineations and deletions. A “copy fair” was duly probated from which no appeal was taken. The will and its codicils were interpreted by the auditing judge to bequeath the residue of the testator’s estate, in trust, for the benefit of his widow for life and, at her death, 61% thereof to pass to certain named charities and the remaining 39 % of such residue to continue in trust for the benefit of testator’s four children, for their respective lives, with remainder to their issue. The will also contains a provision that all death taxes be paid from the *196residue of the state with authority to the executors to prepay such taxes on future interests.
During the period of administration the executors paid federal estate taxes in the sum of $121,477.21 and Pennsylvania transfer inheritance taxes “on account” in the sum of $35,123.20. Thereafter, on August 22, 1973, pursuant to Section 714(a) 1 of the Pennsylvania Inheritance and Estate Tax Act of 1961, as amended, the executors filed an election to prepay the Pennsylvania inheritance taxes on the future interests in the 39% of the residue which, after the widow’s death, would ultimately vest in possession in the testator’s descendants.
Pursuant to such election, the Commonwealth’s appraiser valued such remainder interests, as of the date of such election, at the sum of $457,415.16. This amount constituted (1) $300,814.75 or the undisputed value of the assets existing and present in the residuary trust on the date of the election; plus (2) the previously paid federal estate and Pennsylvania inheritance taxes. This created a tax liability of $131,644.31. It is the estate’s contention that it was error for the Commonwealth to add back the previously paid federal estate and Pennsylvania inheritance taxes, and that the estate’s tax liability should be determined solely by reference to the value of the residuary trust on the date of the election.
*197From this valuation by the Commonwealth the estate filed a protest to the Inheritance Tax Board; 2 and a decision by the Protest Board was rendered on December 21, 1973, sustaining the valuation of the Commonwealth. The estate appealed the Board’s decision to the Court of Common Pleas of York County, Orphans’ Court Division, as provided by Section 1003 of the Inheritance and Estate Tax Act of 1961, Act of June 15, 1961, P.L. 373, Art. X, § 1003, 72 P.S. § 2485-1003. The court in an able opinion sustained the estate’s contention and modified the appraiser’s valuation, holding that it was error for the Commonwealth’s appraiser to add back the federal estate taxes in fixing the value of the remainder interests and that it was also error for the appraiser to add back the Pennsylvania inheritance taxes unless a portion of those taxes was paid on account. 24 Fiduc. Rep. 459 (1974). This appeal followed.3
The Commonwealth contends here, as it did before the Court of Common Pleas of York County, that in deter*198mining the value of the aforesaid remainder interest for inheritance tax purposes, all federal estate and Pennsylvania inheritance taxes theretofore paid must be included, i. e., added back, to increase the total value of the taxable remainder given to the Miller Estate residuary trust. The resolution of this issue depends upon the correct interpretation of the Inheritance and Estate Tax Act of 1961, Act of June 15, 1961, P.L. 373, 72 P.S. §§ 2485-714(a), as amended, and 2485-651. This Act is applicable to estates of decedents dying after January 1, 1962.
Under the Pennsylvania Inheritance and Estate Tax Act of 1961, the tax on a future interest may be paid in any of three ways. First, under Section' 713(a), as amended:
“At any time within nine (9) months after the decedent’s death, the personal representative or any party in interest may elect, by a writing filed with the register, to have the value of a future interest determined as of the date of decedent’s death and to pay the tax assessed thereon.”
Second, pursuant to Section 506, the remaindermen may have the interest valued and pay tax thereon as of the date the interest takes effect in possession and enjoyment. Third, under Section 714(a), as amended, the fiduciary, any time following nine months of decedent’s death and prior to the future interest taking effect in possession and enjoyment, may elect to prepay the tax on the future interest.
The executors in this case chose to prepay the tax on the residuary trust pursuant to Section 714(a), as amended.4 In conjunction with Sections 713 and 714, as amended, Section 506 of the Act sets forth the valuation date of a future interest as the date it takes effect in possession and enjoyment or, if an election to prepay is made after nine months of decedent’s death, then the *199date of said election.5 The Commonwealth is now contesting the conclusion of the court below that no previously paid federal estate tax and Pennsylvania inheritance tax assessed on the prior possessory interests should be added back when computing the value of the remainder interest as of the election date.
The Commonwealth bases its add-back theory in its brief on Section 651 of the Act, which provides:
“E. Future Interests — Cost and Taxes — Deductible
All reasonable expenses of administration, incurred after assessment of the inheritance tax on prior interests, and all death taxes paid out of property supporting such prior interests, shall not be included in the appraisement in determining the value of a future interest on the valuation date. This section shall not apply when the tax is paid under the provisions of sections 713(a) and 714(a).”
Act of June 15, 1961, P.L. 373, Art. VI, § 651, 72 P.S. § 2485-651. Thus, the Commonwealth contends that on the date of valuation of the remainder interest the failure to add in prepaid death taxes amounted to an im*200proper deduction under Section 651. The court below did not agree. We affirm.
In analyzing this issue we must examine the statutory predecessors to the present Act and our relevant case law. The predecessor to the Inheritance and Estate Tax Act of 1961 was the Act of June 20, 1919, P.L. 521, as amended, 72 P.S. § 2302, which is no longer applicable to persons dying on or after January 1, 1962. Section 2 provided:
“All taxes imposed by this act shall be at the rate of [fifteen] per centum upon the clear value of the property subject to such tax passing to . [collaterals] . . . . In ascertaining the clear value of such estates, the only deductions to be allowed from the gross values of such estates shall be the debts of the decedent and expenses of the administration of such estates, and no deduction whatsoever shall be allowed for or on account of any taxes paid on such estates to the Government of the United States or to any other State or Territory.”
Section 3 of the Act governed the assessment of inheritance tax upon the value of the future interest at the time the right of possession accrues to the owner.
“Where there is a transfer of property, by a . bequest . . . liable to the tax hereinbefore imposed, which . . . bequest . . . is to take effect in possession or to come into actual enjoyment after the expiration of any one or more life-estates or a period of years, the tax on such estate shall not be payable, nor shall interest begin to run thereon, until the person liable for the same shall come into actual possession of such estate by the termination of the estates for life or years. The tax shall be assessed upon the value of the estate at the time the right of possession accrues to the owner, but the owner may pay the tax at any time prior to his coming into possession. In such cases the tax shall be assessed on the *201value of the estate at the time of the payment of the tax, after deducting the value of the life-estate or estates for years. . . . ”
In Pickering Estate, 410 Pa. 638, 190 A.2d 132 (1963), this Court was faced with a factual situation similar to the case at bar which necessitated an interpretation of these predecessor statutes to the current Inheritance and Estate Tax Act. In Pickering the executor first paid the inheritance tax “due by reason of present interests under Pickering’s will.” 410 Pa. at 641, 190 A.2d at 133. Some time later, pursuant to Section 3 of the Inheritance and Estate Tax Act of 1919, he chose to prepay the tax on the remainder interests left under the will. The problem as Mr. Chief Justice Bell presented it was as follows:
“The Commonwealth claimed a collateral inheritance tax on the remainder set apart for Anna’s children [testator’s niece’s children] and issue based upon the value of their remainder interest at the date of testar tor’s death [December 7, 1955]. The executor on the other hand contended that the tax should be based upon a taxable value of the gifts in the remainder, computed as of February 9, 1959 instead of the date of testator’s death. More specifically, the Commonwealth contends that in determining the value of the aforesaid remainder interest for inheritance tax purposes, all Federal Estate taxes theretofore paid must be included, i. e., added back, to increase the total value of the taxable remainder given to Anna’s children and issue.”
410 Pa. at 641-42, 190 A.2d at 133-34.
In valuing the remainder interest in Pickering Estate, the Court relied upon the language in Simpson’s Estate, 332 Pa. 115, 2 A.2d 851 (1938), where we stated:
“Section 3 of the act provided that ‘the tax . shall not be payable . . . until the person or persons liable for the same shall come into actual possession of such estate, by the termination of the estates for life or years, and the tax shall be assessed upon the *202value of the estate at the time the right of possession accrues to the owner as aforesaid.’ The party entitled to the subsequent interest is given a choice, however, ‘to pay the tax at any time prior to his coming into possession, and, in such cases, the tax shall be assessed on the value of the estate at the time of the payment of the tax, after deducting the value of the life estate or estates for years.’ ”
382 Pa. at 117, 2 A.2d at 852. See also Carver Estate, 422 Pa. 609, 222 A.2d 882 (1966); Heberton’s Estate, 51 Pa.D. & C. 285, 295 (1944), aff'd per curiam, 351 Pa. 564, 568, 41 A.2d 654, 656 (1945).
Thus, the Court in Pickering Estate, supra, concluded that when the tax is prepaid under Section 3 the value of the remainder is determined as of the date of payment of the tax. In answering the Commonwealth’s contention that Such a method of valuation would result in an impermissible deduction under Section 2, unless the previously paid federal estate taxes were added back, the Court quoted with approval part of the opinion in Oberdorfer Estate, 20 Pa.D. & C.2d 719, 735, 10 Fiduc.Rep. 358, 375 (1960):
“The argument that in this case we are concerned with ‘deductions’ ■ ... is without merit. The Commonwealth attempts to add something to the value of the estáte being taxed. The taxpayer does not claim a deduction.”
410 Pa. at 645, 190 A.2d at 135.
Accordingly, this Court held that it was error for the Commonwealth to add back previously paid taxes where a taxpayer elected under Section 3 to prepay thé tax on his remainder interests. While the legislature repeatedly amended the Act of 1919 after its enactment, it never changed Section 3 or any part thereof until 1961.6 On *203the contrary, when in 1951 the Department of Revenue sponsored House Bill H-1361 to amend Section 3 of the Inheritance and Estate Tax Act of 1919 so that its language would compel the construction urged by the Commonwealth in Pickering Estate, and in the instant case, the bill did not pass. Pickering Estate, 410 Pa. at 638, 190 A.2d at 137.7 Thus, in analyzing the current Section 714(a) and its interplay with Section 651, we are confronted with a long statutory history where the legislature by express action has approved the practice of not including federal estate tax in appraising a future interest such as here at issue.
In determining the tax effect of prepayment and valuation under Section 714(a) of the current Act, we are also faced with a clear mandate from the legislature that our prior construction of its statutory predecessor, Section 3 of the Act of 1919, is to prevail. The comment to Section 714(a) in the Joint State Government Commission Report on the Inheritance and Estate Tax Act of 1961, as amended, states:
“This subsection, in conjunction with Section 506, is in conformity with existing law insofar as it permits prepayment of tax on future interest, at the value of such interest determined as of the date election is made to prepay the tax: Act of 1919, P.L. 521, § 3, as amended.”
The legislative intent and language providing for the valuation and payment of the tax pursuant to Section 714(a), as amended, “could not be clearer; and no reference whatsoever is made therein to the subject of deduct*204ing or ‘adding back’ Federal [or other state] taxes in determining the taxable ‘value of the estate at the time of the payment of the tax.’ ” Pickering Estate, 410 Pa. at 643, 190 A.2d at 134. Thus, our prior holding in Carver Estate, 422 Pa. 609, 222 A.2d 882 (1966), where, in construing the 1919 statute, we held that the appropriate time for appraising an interest postponed in possession or enjoyment until the expiration of a life estate for years is either at the time the remainderman exercises his statutory option to prepay the tax, or, absent such election, at the time the remainderman comes into actual possession or enjoyment, is applicable to the construction of the statute currently before us.
The Commonwealth would have us disregard the statutory directions of Sections 506 and 714(a), as amended, by a construction of Section 651 which would compel executors to add previously paid taxes in order to properly value the estate if they choose an election under Section 714(a), as amended. As we stated in Pickering Estate, that argument is without merit. 410 Pa. at 645, 190 A.2d at 135. Faced with a clear statute which instructs one in the proper method of valuation, without any reference that the failure to add prepaid taxes would achieve an improper valuation by taking an impermissible deduction, the Commonwealth’s strained construction of Section 651 is difficult to maintain. We find no deduction here at all. See Pickering Estate, supra; Penn Trust, 285 Fiduc.Rep. 299 (1975); Oberdorfer Estate, supra.
The language in Section 651 is perhaps less susceptible to the Commonwealth’s construction than was its statutory predecessor, Section 2 of the Act of June 20, 1919. The latter statute clearly precluded the deduction of federal taxes. Yet, faced with the clear valuation language in Section 3 and absent the positive direction that an add back of prepaid taxes was necessary to arrive at a proper valuation of the estate, we held in Pickering Estate, *205supra, that the language in Section 2 did not require the Commonwealth’s construction. As with Section 2, Section 651 provides no command that the Commonwealth’s construction is required.8
We agree with the court below that the last sentence of Section 651 excludes from its application Section 713(a), as amended, because the valuation date in Section 713(a), as amended, is the date of the decedent’s death, which is before an estate’s assets can be reduced by payment of death taxes and when deductions are relévant. See Pickering Estate, supra. In light of the legislative history and our prior case law, the exclusion of Section 714(a), as amended, from the application of Section 651, acts to prohibit the deduction of death taxes from the valuation of the future interest where the election to prepay is filed after nine months from a decedent’s death but before death taxes may have been paid from the estate’s assets. Cf. Baylis Estate, 36 Pa.D. & C.2d 590, 15 Fiduc.Rep. 490 (1965).
Furthermore, if there were any reasonable doubt in this case as to the proper construction of the Act of 1961, as amended, and we think none exists, the legislature has directed that all doubts should be resolved in favor of the taxpayer and most strongly against the taxing authorities. Act of May 28, 1937, P.L. 1019, Art. IV, § 58, 46 P.S. § 558; Mastrangelo v. Buckley, 433 Pa. 352, 250 A. 2d 447 (1969); Pickering Estate, supra.
The final argument presented by the Commonwealth is that the Court’s interpretation of Section 714(a), as amended, would result in non-uniform taxes in violation of Article VIII, Section 1, of the Pennsylvania Constitution. The non-uniformity results, the Commonwealth argues, because a different tax figure will be obtained *206depending upon which election is chosen by the estate. We believe this argument to be without merit.
“ ‘Uniformity requires substantial equality of tax burden [citations omitted]. While taxation is not a matter of exact science and perfect uniformity and absolute equality in taxation can rarely ever be attained [citation omitted], the imposition of taxes which are to a substantial degree unequal in their operation or effect upon similar kinds of business or property, or upon persons in the same classification, is prohibited [citations omitted]. Moreover while reasonable and practical classifications are justifiable where a method or formula of computing a tax will, in its operation or effect, produce arbitrary or unjust or unreasonably discriminatory results, the constitutional provision relating to uniformity is violated [citations omitted].’ ”
Amidon v. Kane, 444 Pa. 38, 48-9, 279 A.2d 53, 59 (1971).
In this case the legislature’s tax upon future interests is uniform because every future interest, without exception, is subject to the tax imposed by the Inheritance and Estate Tax Act of 1961, as amended. Since every future interest is subject to the same valuation options, it insures equality of tax burdens and benefits. This is not a case like Kelley v. Kalodner, 320 Pa. 180, 181 A. 598 (1935), Saulsbury v. Bethlehem Steel Co., 413 Pa. 316, 196 A.2d 664 (1964), or Amidon v. Kane, supra, where, because the taxing scheme either gave non-uniform exemptions or a graduated rate or both, we found it was non-uniform and thus constitutionally deficient. Under the Inheritance and Estate Tax Act of 1961, as amended, every future interest is subject to the same statutory scheme.
Decree affirmed. Costs on appellant.
MANDERINO, J., did not participate in the consideration or decision of this case. *207POMEROY, J., filed a dissenting opinion.. Section 714(a) of the Inheritance and Estate Tax Act of 1961, as amended, provides:
“Payment Date; future interest; payment after nine (9) months from Decedent’s Death; contingencies (a) Payment After Nine (9) Months from Decedent’s Death. At any time after nine (9) months from the decedent’s death, and prior to the vesting of a future interest in possession and enjoyment a fiduciary, or any party in interest, may elect, by a writing filed with the register, to have the value of a future interest determined as of the date of the filing of such election and to pay the tax assessed thereon. Such tax shall become delinquent at the expiration of three (3) months from the filing of the election.”
Act of June 15, 1961, P.L. 373, Art. VII, § 714, 72 P.S. § 2485-714, as amended, Act of June 17,1971, P.L. 173, No. 15, § 1.
. Pursuant to Act of June 15, 1961, P.L. 373, Art. X, § 1001(1), 72 P.S. § 2485-1001(1).
. Pursuant to Act of July 31, 1970, P.L. 673, Art. II, § 202(3), 17 P.S. § 211.202(3).
While no exceptions were taken to the Orphans’ Court’s decree by the Commonwealth, the Commonwealth’s failure to file exceptions does not constitute a waiver under Dilliplaine v. Lehigh Valley, 457 Pa. 255, 322 A.2d 114 (1974). Section 7, Rule 1, of this Court’s Orphans’ Court Rules provides:
“Exceptions
Exceptions shall be filed at such place and time, shall be in such form, copies thereof served and disposition made thereof as local rules shall prescribe.”
In accordance with this section York County adopted Rule 75.1. That Rule provides:
“No exceptions shall be filed to orders or decrees entered unless the right to except is expressly conferred by Act of Assembly, by general rule, or unless specifically allowed in the order or decree, and all decrees other than those to which exceptions are so allowed shall be final.”
Since no right to except was expressly conferred and since the lower court’s decree did not specifically allow the parties to file exceptions, the failure of the Commonwealth to file exceptions in this case cannot be deemed a waiver of the issues now under consideration.
. See footnote 1, supra.
. Section 506 of the Inheritance and Estate Tax Act of 1961 provides:
“Valuation date; future interest
Except as otherwise expressly provided in this act, the valuation date of a transfer of any interest in property to take effect in possession and enjoyment after the expiration of one or more interests for a term of years, for life, or for other limited period, shall be the date of such interest takes effect in possession and enjoyment. The tax shall be computed upon the value of the interest at such date. Except as otherwise expressly provided, when the tax on the future interest is paid prior to its taking effect in possession and enjoyment, the tax shall be computed upon the value of the interest at such date. Except as otherwise expressly provided, when the tax on the future interest is paid prior to its taking effect in possession and enjoyment, the tax shall be computed upon the value of the interest in the property at the applicable date specified in section 713 or 714, diminished by the then value of the preceding limited estate or estates, as determined under the appropriate sections oí tills Article **
Act of June 15, 1961, P.L. 373, Art. V, § 506, 72 P.S. § 2485-506.
. The 1961 Act is the predecessor of the statute which applies in the instant case. It is identical in all respects except that the *2031971 amendments changed the one-year provision in the 1961 Act to nine months in both Sections 713(a) and 714(a).
. The proposed “Inheritance and Estate Tax Act of 1959,” House Bill 1195 of the 1959 session of the legislature, was a substantial equivalent of the Inheritance and Estate Tax Act of 1961. However, due to a controversy over inclusion of Article XI, which set up restrictions for entry into the safe deposit box of a decedent, the bill was defeated.
. Our construction today is in accord with our observations in Pickering Estate, 410 Pa. at 648-50, 190 A.2d at 139. See also Smith and Grossman, Pa. Inheritance and Estate Tax, § 651-2, at 50 (1971).