Your brother is celebrating his 40th birthday today. Planning to retire at the age of 60, he decides to make equal annual deposits into a new savings account on each birthday beginning from his 41st birthday (last deposit on his 60th birthday). The savings account offers 10% interest rate per year, compounded annually. He wants to be able to withdraw $20,000 from his savings account on each birthday for 10 years following his retirement, the first withdrawal will be on his 61st birthday. How much should each annual deposit be so that he will be able to make $20,000 withdrawals after retirement?