A forest farm originally planned to afforest 12 hectares last year, but actually afforested 15 hectares. By what percentage has the actual afforestation increased compared to the original plan?
某林场去年原计划造林12公顷，实际造林15公顷．实际造林比原计划增加了百分之几？
<gadget id="calculator">15 - 12</gadget>
<output>3</output>

<gadget id="calculator">3 / 12</gadget>
<output>1/4 = around 0.25</output>

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