The plaintiffs, the New Hampshire Association of Counties and Belknap, Carroll, Cheshire, Coos, Grafton, Hillsborough, Merrimack, Rockingham, Strafford and Sullivan Counties, individually, appeal from the Trial Court’s (Conboy, J.) order granting summary judgment in favor of the defendants, the State of New Hampshire and the Commissioner of the New Hampshire Department of Health and Human Services (collectively, the State). We affirm.
The record supports the following. In 1998, the legislature passed what is referred to by the parties as SB 409, which was aimed at reforming the system for delivering and paying for long-term care for the indigent elderly and disabled. See Laws 1998, ch. 388. Prior to the enactment of SB 409, the counties had been responsible for paying for certain portions of Old Age Assistance (OAA) and Aid to the Permanently and Totally Disabled (APTD) for those in nursing homes, as well as for making a Local Medical Assistance Contribution (LMAC) relating to the same people. See RSA 167:18-a, :18-b, :18-f (1994). Under SB 409, in addition to these and other required payments, the counties became liable for paying a share of the cost of medical care for those persons eligible for nursing home care, but who receive care under a Home and Community Based Care (HCBC) waiver. See Laws 1998,388:8. SB 409 contained a “sunset” provision stating *287that RSA 167:18-b and RSA 167:18-f, which defined the OAA, APTD and LMAC payments, would be repealed on June 30, 2003. Laws 1998, 388:16, I, II, :17, II. In order for the relevant portions of SB 409 to take effect, SB 409 expressly provided that county approval was required. Laws 1998, 388:10. The counties approved SB 409. Since that time, the State has extended the sunset provision, most recently from 2007 to 2013. See Laws 2007,263:17, :25, :26. There is no dispute about the State having delayed the sunset from 2003 to 2007.
In 2005, the legislature passed Laws 2005, chapter 177, which increased the amount of the counties’ LMAC payments. Laws 2005, 177:13. In 2007, the legislature passed Laws 2007, chapter 263 (chapter 263), which realigned and consolidated the statutory scheme governing the relationship between the counties and the State as regards financial support for the indigent elderly and disabled. See Laws 2007, ch. 263. As a result of the passage of chapter 263, RSA 167:18-b was repealed, but nearly all of its provisions were incorporated into RSA 167:18-a. See RSA 167:18-a (Supp. 2008). As to the financial impact of the changes under chapter 263, for fiscal year 2008, little changed between the counties and the State. Laws 2007, 263:17. For fiscal years 2009 through 2013, however, the county share for nursing home and HCBC care for OAA and APTD recipients was raised from fifty to one hundred percent of the share not covered by federal Medicaid payments. Id. For fiscal years 2009 and 2010, chapter 263 contains a “hold harmless” provision ensuring that the counties will not be required to pay more than they paid under the prior statutory funding scheme established by RSA 167:18-b prior to its repeal. Id. For fiscal years 2011 through 2013, there is no “hold harmless” provision, but the statute provides that caps on billings to the counties “shall be established” by the legislature for those years. Id. Chapter 263 also repealed RSA 167:18-f effective July 1, 2008. Laws 2007, 263:24.
In August 2007, the plaintiffs brought suit in superior court seeking an injunction barring the enforcement of some of the above-referenced statutes, and a declaratory judgment that the statutes violated Part I, Article 28-a of the New Hampshire Constitution. The trial court denied the injunction and, on cross-motions for summary judgment, ruled in favor of the State, concluding that the statutes did not violate the constitution. The plaintiffs now appeal, arguing that the extensions of the sunset provision contained in SB 409, the increase in the counties’ share of nursing home and HCBC care costs pursuant to chapter 263, and the 2005 increase in their LMAC obligations, all violate Article 28-a.
“In reviewing the trial court’s summary judgment rulings, we consider the evidence in the light most favorable to each party in its capacity as the nonmoving party and, if no genuine issue of material fact exists, we *288determine whether the moving party is entitled to judgment as a matter of law.” N.H. Assoc. of Counties v. Comm’r., N.H. Dep’t of Health & Human Servs., 156 N.H. 10, 14 (2007). The sole issue on appeal is whether the challenged legislative enactments violate Part I, Article 28-a of the New Hampshire Constitution. We review the constitutionality of the statutes de novo. See Baines v. N.H. Senate President, 152 N.H. 124, 133 (2005).
In reviewing a legislative act, we presume it to be constitutional and will not declare it invalid except upon inescapable grounds. N. Country Envtl. Servs. v. State of N.H., 157 N.H. 15, 18 (2008). In other words, we will not hold a statute to be unconstitutional unless a clear and substantial conflict exists between it and the constitution. Id. When we are required to interpret a provision of the constitution, we view the language used in light of the circumstances surrounding its formulation. N.H. Munic. Trust Workers’ Comp. Fund v. Flynn, Comm’r, 133 N.H. 17, 21 (1990). We give the words in question the meaning they must be presumed to have had to the electorate when the vote was cast. Id.
Adopted in 1984, Article 28-a provides:
The state shall not mandate or assign any new, expanded or modified programs or responsibilities to any political subdivision in such a way as to necessitate additional local expenditures by the political subdivision unless such programs or responsibilities are fully funded by the state or unless such programs or responsibilities are approved for funding by a vote of the local legislative body of the political subdivision.
N.H. CONST. pt. I, art. 28-a. We have stated that this amendment “was designed to provide a safety net to save cities and towns from the burden of coping with new financial responsibilities, not of their own creation, and to permit them a stronger grasp of their fiscal affairs.” Flynn, 133 N.H. at 27. To that end, the amendment “was designed to prohibit the State from placing additional obligations on local government without either obtaining their consent or providing the necessary funding.” Id. at 22; see also Opinion of the Justices (Voting Age in Primaries), 157 N.H. 265, 273 (2008). The “constitutionality of a particular State mandate under article 28-a does not hinge solely on whether or not it may be categorized as a new, expanded or modified program, but also on whether or not the mandate imposes upon local government an additional fiscal obligation.” Flynn, 133 N.H. at 23. “Increased expenditures alone are not dispositive of whether a program or responsibility has been expanded.” Town of Nelson v. N.H. Dep’t of Transportation, 146 N.H. 75, 78 (2001). “The primary consideration is the net effect of the program.” Opinion of the Justices (Solid Waste Disposal), 135 N.H. 543, 545 (1992). In the end, the invocation of this *289provision “requires both a mandate of responsibility to the political subdivision and a requirement of additional local political subdivision expenditures by virtue of the mandate.” Nelson, 146 N.H. at 78.
In reviewing the net effect of the enactments at issue, we conclude that no new, expanded or modified program or responsibility has been enacted, or, to the extent it has, there is no requirement of additional local expenditures and thus no violation of Article 28-a. Prior to the adoption of Article 28-a in 1984, the counties were required to pay for fifty percent of the share of providing the relevant programs that was not paid by the federal government through the Medicaid program. See RSA 167:18, :18-a, :18-b (1977). Though the percentages varied at times, see, e.g., RSA 167:18-b (1994), the obligation to pay fifty percent was continued in 1998 with the passage of SB 409, see Laws 1998, 388:8, and again continued through the passage of chapter 263. See Laws 2007, 263:17. Thus, at the dates most significant to the legislation at issue, the net effect has been merely to continue an obligation in existence prior to the adoption of Article 28-a.
The counties contend, however, that Laws 2007, 263:25, which extended the sunset provisions contained in SB 409, violates Article 28-a because it mandated a new obligation for county payments after the obligation was to cease. According to the counties, the sunset provision was intended to end their obligation to pay for these programs in 2007, and thus the extension created a new obligation to make payments beyond 2007. Alternatively, the counties contend that if the payment requirement did not create a new obligation, it is at least an expansion or modification of the prior payment obligation. The State counters that this is a long-standing obligation which is not defined by reference to a particular date. The State also contends there was no intent to end the obligation and that a change in the repeal date does not create a new, or alter the old, obligation.
While the mere existence of a historical obligation does not automatically render the counties liable for continued payments, we note that the counties have had some obligation to pay for these services for more than 200 years. See, e.g., Act of January 22, 1790 reprinted in 5 LAWS OF NEW HAMPSHIRE 502 (1916). It might, therefore, seem unreasonable to interpret the sunset provision as having been intended to terminate such a longstanding obligation. Nevertheless, the counties contend that with the passage of the sunset provision in SB 409, their obligation was to terminate. We reject this argument for two reasons. First, as a technical matter, SB 409 provided that RSA 167:18-b would be repealed on a particular date, and, in fact, RSA 167:18-b has been repealed. See Laws 2007,263:24. Thus, *290the statute’s repeal provision has been given effect, and shifting of the obligation to RSA 167:18-a does not somehow undo the sunset.
Second, nothing in the language of SB 409 indicates that the repeal of RSA 167:18-b would end the counties’ financial obligation. Essentially, the effect of the sunset provision, if it had not been extended, would have been to reset the amount of the obligation, not eliminate it. The counties contend that “under the law as it stood prior to the enactment of Chapter 263, there was no statute which required the counties to pay these costs.” However, RSA 166:l-a (2002), which is unchallenged by the counties, states that the counties will be required to reimburse the State for these services at an amount determined by the legislature. RSA 167:18-b then set the amount and timing of the payments. The repeal of RSA 167:18-b thus would not end the obligation. Because the extension of the repeal date is merely a continuation of an obligation predating the enactment of Article 28-a, chapter 263’s extension of the sunset does not violate Article 28-a. See Town of Nelson, 146 N.H. at 79.
The counties argue that this logic cannot be used to defend the HCBC payments because such payments did not exist until the passage of SB 409 in 1998, and thus do not predate Article 28-a. HCBC payments, however, are made for those eligible for nursing home care but who do not receive care in an actual nursing home. Laws 1998, 388:8. The counties do not dispute that they have had an existing obligation to pay for those eligible for nursing home care. The HCBC payments are thus little more than a redirection of payments already owed.
The counties also contend that because SB 409 required their approval, after they approved it the State was bound by its repeal language and could not unilaterally alter the obligation. The legislature, however, has authority to amend any statute, consistent with the constitution. The counties’ agreement, while a statutory precondition for SB 409 to become fully effective, did not prevent the legislature from later amending the statutes to continue the counties’ pre-existing obligation past a time the counties may have believed it would end. In other words, the counties’ belief did not dictate State action.
The counties next argue that the State violated Article 28-a when, pursuant to Laws 2007, 263:17, it expanded the counties’ payment obligations of OAA, APTD and HCBC from fifty to one hundred percent of the non-federal share through at least 2013. We conclude that Article 28-a has not been violated because even presuming that the change in the county obligation from fifty to one hundred percent of the non-federal share is a new, expanded or modified obligation, we agree with the State that the alteration does not impose a greater cost upon the counties. As stated *291previously, the “constitutionality of a particular State mandate under article 28-a does not hinge solely on whether or not it may be categorized as a new, expanded or modified program, but also on whether or not the mandate imposes upon local government an additional fiscal obligation.” Flynn, 133 N.H. at 23. Under chapter 263, for fiscal years 2009 and 2010, “no county shall be liable for total billings ... in an amount which would be greater than the amount of liability projected for that fiscal year using the methodology for determining county payments in former RSA 167:18-b prior to its repeal.” Laws 2007, 263:17. Thus, regardless of the obligation, for those fiscal years there is no additional fiscal requirement upon the counties and no violation of Article 28-a. Indeed, the counties appear to concede as much.
As regards fiscal years 2011 through 2013, the remaining operative years of chapter 263, the law states that caps on total billings shall be established by the legislature. Laws 2007, 263:17. Thus, we assume that pursuant to chapter 263, the legislature intends to establish caps on county spending, at a later date. We agree with the trial court that in light of this provision, the fiscal obligation of the counties in 2011 through 2013 is speculative. Because there must be a clear and substantial conflict with the constitution to declare a legislative act unconstitutional, N. Country Envtl. Servs., 157 N.H. at 18, we cannot say at this time that chapter 263 violates Article 28-a.
The counties argue that, “The State provided no evidence below to dispute the county affidavits which said that, as Chapter 263 stands, the new law will cost the counties more money in [fiscal years] 2011-2013 than would have been the case had Chapter 263 not been enacted.” Therefore, they argue the trial court “should have effectuated the purpose of the declaratory judgment statute and afforded the parties relief from uncertainty and insecurity created by doubt as to rights, status or legal relations.”
Although the affidavits submitted by the counties state that the costs of the items for which the counties must pay will increase, they do not account for the caps called for by the statute which may eliminate any potential constitutional violation. Until it is known whether there will, in fact, be an increase in required county spending, a judgment as to the statute’s constitutionality is unwarranted. While the declaratory judgment statute, RSA 491:22 (1997), is meant to relieve parties of uncertainty about their rights, see Werme’s Case, 150 N.H. 351, 353 (2003), we conclude that the uncertainty surrounding potential cost increases does not create a clear and substantial conflict with the constitution. Accordingly, the issue is not ripe for review.
*292Lastly, the counties contend that Laws 2005, chapter 177, which increased the counties’ obligations under the LMAC, violates Article 28-a. We conclude that the issue is moot. The LMAC was required by RSA 167:18-f, which was repealed effective July 1, 2008. See Laws 2007, 268:24. It does not appear to have been reenacted in any other form. Generally a matter is moot when it no longer presents a justiciable controversy because issues involved have become academic or dead. Londonderry Sch. Dist. v. State, 157 N.H. 734, 736 (2008). A challenge seeking only prospective or declaratory relief is generally mooted where intervening legislative activity renders the prior law inapplicable. Id. Because the law challenged by the counties has been repealed and not reenacted elsewhere, and because the counties sought only declaratory relief relative to that law, we conclude that this issue is moot.
Affirmed.
Broderick, C.J., and Dalianis and Hicks, JJ., concurred; Duggan, J., concurred specially in part and dissented in part.