1 The phase usually lasts up to 10 minutes.  You will be in light sleep in the second stage of a non-REM sleep. Your heart rate will come down and so will your body temperature. You will soon enter deep sleep phase.
Keep records for 3 years from the date you filed your original return or 2 years from the date you paid the tax, whichever is later, if you file a claim for credit or refund after you file your return. Keep records for 7 years if you file a claim for a loss from worthless securities or bad debt deduction. Keep records for 6 years if you do not report income that you should report, and it is more than 25% of the gross income shown on your return. Keep records indefinitely if you do not file a return.
Still, you'd be surprised at how much you can safely discard. Here is what you should keep and how long you should keep it. Three Years. Keep your federal and state income tax returns and related receipts and statements for at least three years. If you are audited, the IRS reserves the right to review tax returns filed during what is known as the period of limitations, which is generally the past three years from the date you filed your most recent tax returns.