A factory’s water bill increased by 5% last year compared to the previous year. This year, water saving measures are adopted, and the water bill is expected to decrease by 5% compared to last year. What is the estimated percentage of this year's water bill compared to the previous year?
某工厂去年水费比前年增加5%，今年采取节水措施，水费预计比去年减少5%．预计今年水费是前年的百分之几？
<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 + (1/20)</gadget>
<output>21/20 = around 1.05</output>

<gadget id="calculator">1 - (1/20)</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">(21/20) * (19/20)</gadget>
<output>399/400 = around 0.9975</output>

<result>399/400 = around 0.9975</result>