Mark is saving for his child$$s education. Initially, he contributed $$15,000$ into his savings account in the first year. However, due to rising expenses, he decides to decrease his annual contribution by $$500$ each subsequent year. At the end of $5$ years, Mark wonders: If he would have contributed an equal amount every year instead of decreasing the amount over time, how much should he have contributed annually starting at the end of year $1$ to have the same accumulated amount at the end of $5$ years, assuming an annual interest rate of $6\%?.$Find the equivalent equal payment series for Mark's gradient contribution series. Answer to the nearest dollar.