Deposit 500 yuan in a commercial bank, and after one year, the total will be 509.90 yuan with the principal and interest. What is the annual interest rate of this deposit?
在商业银行存入500元，一年后连本带息共509.90元，这笔存款的年利率是多少
<gadget id="calculator">509.9 - 500</gadget>
<output>9.9</output>

<gadget id="calculator">9.9 / 1 / 500</gadget>
<output>0.0198</output>

<result>0.0198</result>