Matusek Corporation has been experiencing a higher than expected number of warranty claims in the current year, due mainly to less than ideal product design. For this reason, the warranty expense percentage used was changed from 2% to 3% of sales. The warranty expense for the current year was calculated using the new rate of 3% of sales. The controller estimates that if the new rate had been used in the past, an additional $150,000 worth of warranty expense would have been recorded. 

(a) Does this change require a change in accounting policy?

(b) What journal entry, if any, should Matusek record at the end of the fiscal year ending December 31, 2020?