Subscribe to Entrepreneur for $5Signing out of account, Standby...The "Rule of 25" is a good starting point to find your number.ByOctober31, 2019Opinions expressed by Entrepreneur contributors are their own.Have you taken the time to run the numbers and determine exactly how much you need to save for ? Have you looked at how much you have saved so far and calculated how many years that money will last? If you've gotten serious in your retirement planning, you may have spent some restless nights calculating and recalculating just how much money you'll need during your elder years and...…Subscribe to Entrepreneur for $5Signing out of account, Standby...The "Rule of 25" is a good starting point to find your number.ByOctober31, 2019Opinions expressed by Entrepreneur contributors are their own.Have you taken the time to run the numbers and determine exactly how much you need to save for ? Have you looked at how much you have saved so far and calculated how many years that money will last? If you've gotten serious in your retirement planning, you may have spent some restless nights calculating and recalculating just how much money you'll need during your elder years and...WW…