Hi progressing pythonistas-- Playing with the interpreter I came up with this: >>> a = [66.6, 333, 333, 1, 1234.5] >>> print a.count(333), a.count(66.6), a.count('y') 2 1 0 >>> a.insert(2, -1) >>> a.append(333) >>> a [66.599999999999994, 333, -1, 333, 1, 1234.5, 333] Can anyone explain why 0th index came out as it did? Is this a floating point arithmetic issue/limitation? Thanks. Tom Rivas