Justice Stewart’s language in Spannaus evidently evinces less deference to state economic policy decisions affecting private contracts than do the opinions which intervened between Spannaus and Blaisdell. Nevertheless, we do not believe the Span-naus ease furthers the plaintiffs’ cause. The Spannaus Court relied upon a combination of circumstances not presented by the Tenancy Act. Spannaus deals with the modification of an existing contractual relationship voluntarily arrived at by negotiation between employer and employee. The Tenancy Act, in contrast, involves the modification of the terms of a non-contractual statutory tenancy previously imposed by state law. In Spannaus, the Minnesota legislature entered a field it had never before sought to regulate; New Jersey, to the contrary, regulated statutory tenancies following the expiration of a contractual lease beginning in 1974, and the plaintiffs purchased subject to those limitations. The Minnesota legislation, as described by Justice Stewart, did not address a broad generalized social problem. Indeed, there were indications that the legislation intended to single out “a small number of employers ... from the larger group.” Energy Reserve Group, 103 S.Ct. at 708 n. 25. Here the legislative findings and affidavits on file establish that New Jersey — both in the 1974 Anti-Eviction Act and in the 1981 Tenancy Act — dealt with a generalized, extremely serious housing shortage caused by the unavailability of mortgage funds, which placed great economic pressure on owners of rental property to capitalize on that shortage by converting to condominium ownership. Finally, Minnesota singled out the pension contract obligations of employers leaving that state. New Jersey, on the other hand, excluded from the coverage of the Anti-Eviction Act and the Tenancy Act only multiple dwellings with fewer than five units. The Act thereby “imposed a generally applicable rule of conduct designed to advance a broad societal interest.” Exxon Corp. v. Eagerton, -- U.S. --, 103 S.Ct. 2296, 2306, 76 L.Ed.2d 497 (1983).