A factory plans to produce 4,000 parts in October. As a result, the first half of the month completed the plan (5/8), and the second half of the month only completed the same number as the first half of the year. What percentage was actually exceeded this month?
某工厂计划十月份生产零件4000个，结果上半月完成计划的(5/8)，下半月完成的只数与上半年的同样多，这个月实际超额百分之几？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(5/8) - 1</gadget>
<output>-3/8 = around -0.375</output>

<gadget id="calculator">(5/8) + (-3/8)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>