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<html><body>Month and year: <input type="month" id="myMonth" value="1997-11"><p>Click the button to decrement the value of the month field by 3 months (each time you click).</p><button onclick="myFunction()">Try it</button><p><strong>Note:</strong> The stepDown() method is not supported by Firefox.</p><script>function myFunction() { document.getElementById("myMonth").stepDown(3);}</script></body></html>