It is known that the price of a certain model car was 250,000 yuan last year, and this year it is 45,000 yuan lower than last year. What percentage is the decrease this year compared to last year?
已知某型号汽车去年售价25万元，今年比去年降低了4.5万元，今年比去年降低了百分之几？
<gadget id="calculator">4.5 / 25</gadget>
<output>0.18</output>

<result>0.18</result>