Slider reverse Min and Max

Slider reverse Min and Max

I am working on a slider to select a year-based date range.
I need to reverse the Min and Max.... for example;
2009 - 1950 and I need 2009 to be on the LEFT.
I can only get it to go to Right because it's the highst number.
How do I reverse the polarity (so to speak)?
Thanks
JD
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