When and why did Bill Nye the Science Guy get cancelled?

February 20, 1998 is when the last Bill Nye Episode aired that was brand new. Since then it's nothing but reruns. No idea why it was cancelled but I've heard it was due to lack of interest in the show and funding issues. I don't know which is true but I love the show and miss it dearly on TV. Thank goodness I have them all on VHS.