Based on projections from government data, the proposed $15 minimum wage for fast-food workers could represent more than 60 percent of the wage of a typical New York City worker when it takes effect at the end of 2018, though rising wages for middle-income workers could diminish that figure somewhat.

Such a ratio lies at the outer limit of the country’s historical experience with the minimum wage, at least before the recent increases in cities like Seattle and Los Angeles, most of which have yet to be fully phased in.

In 2003, a citywide minimum wage increase in Santa Fe, N.M., was roughly as steep, though it exempted small businesses. In the late 1970s and early 1980s, the local minimum wage stood at over 60 percent of the local median wage in several Southern and low-population states thanks to increases in the federal minimum wage, according to data compiled by Ben Zipperer of the Washington Center for Equitable Growth.

Several economic analyses of the Santa Fe increase suggested it had little effect on employment, while the effects of the earlier increases have not been extensively studied with modern tools.

Still, as ambitious as the proposed increase is for fast-food workers in New York City, it pales in comparison to the increase in the rest of the state, where the new $15-per-hour minimum for fast-food workers would take effect in July 2021. The minimum wage for fast-food workers could rise to 75 percent or more of the wage for a typical worker in a number of cities across the state, like Binghamton, Buffalo and Utica. There is little precedent for an increase of this magnitude.

There are other reasons to believe that employers in expensive cities like New York, San Francisco and Los Angeles are better able to adapt than employers in other cities and less populated areas, economists say.