As banks tighten up on lenders, credit scores are taking a dive.

The number of Americans who are considered a very high credit risks has risen by 5 million to just under 40 million. At the same time, the number of consumers who qualify for the best rates has taken a dive. Analysts say it's because many of those so called superprime borrowers have been late on payments. So as lenders address a shift in credit worthiness, watchdog groups are asking regulators and Congress to make sure that doesn't impair people's overall right to get credit.