Introducing the Weight-tracker spreadsheet (Part 1)

Today I want to introduce my Excel spreadsheet. 

I have developed this tool because I think that accurate measurements are a critical element of success ("If you can't measure it, you can't change it!") . I hope that other people will be able to use it to record their own weight data if they so desire. There are several useful statistical “tricks” lurking behind some of the cells in the spreadsheet which I will explain. The red arrows simply indicate where data needs to be entered.

Column  B (Box 1) is where the date is recorded. Column C (Box2) is where your daily weight measurement is entered. After that everything is automatic. Column D does the subtraction for you so you know how much weight you have lost each day. Column E is called a “five-point moving average.” It simply averages weight-loss over each successive five day period (smoothing out the daily ups and downs) and Column F totals your weight losses. Straight forward, so far?

To the right of Column F is a straightforward graph (shown above) which plots the weight entered each day against the number of days the diet has been running. The blue dotted lines show the theoretical traces for average weight loses of 1 or 1.5, 2 or 2.5 kg per week. The black line is called a regression line.  Excel looks at all your data in Column B and then predicts the rate at which your weight is actually decreasing. This will change slightly  each time you make a new data entry (particularly in the early stages). I have set up my graph so the horizontal axis equates to my goal weight of 95 kg..This means that  I can instantly read off the number of days that it will take me to achieve success based on the latest data

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In my next blog I will explain the third part of the spreadsheet which provides an indication of probable success and I will explain how you can download and customise this spreadsheet.

*Today is day 13 of my weigh-loss project and I am celebrating a weight-loss milestone of 5.4kg.*