According to statistics, the economic loss caused by land desertification in my country reaches 18 billion yuan every four months. Based on this, how many billion yuan is the economic loss caused by land desertification in my country in a year?
据统计，每4个月我国因土地沙漠化造成的经济损失就达180亿元，据此推算我国一年因土地沙漠化造成的经济损失为多少亿元？
<gadget id="calculator">180 / 4</gadget>
<output>45</output>

<gadget id="calculator">45 * 12</gadget>
<output>540</output>

<result>540</result>