The amount of time negative information stays on your credit report depends on which type of debt it is. Thanks to the federal law the Fair Credit Reporting Act, there is a specific time limit allowed by law.
For most types of negative information, a seven year credit reporting limit exists from the date of original delinquency. This includes late payments and collections on credit cards, student loan defaults, and foreclosures. The Higher Education Act specifically deals with student loan defaults.
Certain items may stay on your report for longer than seven years. Charge offs can remain on your report for seven and a half years from the date the creditor charges them off.
Generally they only report for seven years as with delinquent payments.
Judgments and lawsuits vary from seven years from the filing date up to the statute of limitations from the state (whichever is longer). Paid tax liens require seven years from the date you pay them (or to the point you ask the IRS to remove them if they do not do it automatically).
Unpaid tax liens remain on your credit report indefinitely. Bankruptcies require typically seven years from the date of filing though they can stay as long as 10 years from the original filing date. Regardless of the type of bad credit information, you can expect at least seven years of negative impact on your credit report (from the point your creditors start reporting it as negative).