The 7th item The Republicans promised in The Republican Contract with America is
"Require a three-fifths majority vote to pass a tax increase."
This one is VERY simple to grade. It was never accomplished.
The Republicans in Federal office are not currently increasing very many taxes; however, they are tinkering with and making the Federal tax code more and more complex every year. The Federal tax code is well over 60,000 pages at this point.
Status of Contract:
Promises Broken 4
Promises Kept 3