On the first day of school, 998 people from Nanshan Primary School attended the opening ceremony, and only 2 people asked for sick leave. Find the absence rate for this day.
开学第一天，南山小学有998人参加开学典礼，只有2人请病假．求这一天的缺席率．
<gadget id="calculator">998 + 2</gadget>
<output>1_000</output>

<gadget id="calculator">2 / 1_000</gadget>
<output>1/500 = around 0.002</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(1/500) * 1</gadget>
<output>1/500 = around 0.002</output>

<result>1/500 = around 0.002</result>