The age of an ancient artifact can be determined by the amount of radioactive carbon-14 remaining in it. If D_{0} is the original amount of carbon-14 and D is the amount remaining, then the artifact's age A (in years) is given by

A = −8267 ln

D

D_{0}

.

Find the age of an object if the amount D of carbon-14 that remains in the object is 84% of the original amount D_{0}. (Round your answer to the nearest whole number.)