Estimates of the amount of natural gas that can be extracted from U.S. reserves is much too high and the boom may last just half as long as predicted, says a new report in the journal Nature. Official government estimates by the Energy Information Administration (EIA) suggest that peak natural gas production, driven by the rapid growth of hydraulic fracturing, will likely last until 2040 before tapering off. The new analysis suggests that that estimate is too high. Instead, researchers say, the peak will likely come in 2020, and after that production will fall off dramatically. The findings are based on higher-resolution, finer-scale estimates of oil and gas reserves — in units of a single square mile — compared to the EIA’s method, which lumps together all land within a single county. The EIA’s method also fails to account for the realities of economics, the reseachers say: Fracking companies tend to look for “sweet spots,” which they quickly abandon as soon as the reserves become depleted and extraction costs rise.