incorrect acres to ft^2 conversion

[iembry]

Hi, according to Units and Symbols Found in the UDUNITS2 Database, an acre is

unit of area in the US Customary System, used in land and sea floor measurement, equal to 43560 square feet (exact).

If that is true, then the following is incorrect:

library(units)

ad <- with(ud_units, 1 * acre)

ad
1 acre

units(ad) <- with(ud_units, ft^2)

ad
43560.17 ft^2

If the current definition of acres is incorrect within units, then will you correct it then?

Thank you.

Irucka Embry