Each cigarette reduces your life by an estimated 11 minutes according to an article entitled "Time for a smoke? One cigarette reduces your life by 11 minutes" published in 2000. They used the data from a study of 34,000 male doctors over a period of 40 years. They calculated the difference in life expectation between smokers and non-smokers and estimated the total number of cigarettes consumed by a regular male smoker in his lifetime to arrive at the number of 11 minutes per cigarette. It means numbers produced by this calculator is only applicable to male smokers.
Note that estimates in this and similar studies can be very crude and limited by the quality of the data they use. Estimating the effect of each cigarette on a person's life expectancy is very difficult and depends on many factors. So the purpose of this calculator is to give you a crude idea on the effect of smoking on your life expectancy. It should not be used for any medical purposes.
Instructions on how to use time lost due to smoking calculator
Using time lost due to smoking calculator is very simple. It only requires 2 inputs to enter. First input is the total number of years you've been smoking. The second input is the average number of cigarettes you smoke per day. In most countries, there are 20 cigarettes in a pack. So if you are smoking one pack a day on average, enter 20. After you enter an input, either press Enter or click away from that input to trigger calculations.
Number of years lost is calculated based in these two inputs using the algorithm described above.
This calculator was created using SpreadsheetWeb Designer. Here is a video on creating a mortgage calculator with SpreadsheetWeb.