what is the formula for calculating a survey scale of 1-5?

Question

I did a survey and the respondents had a choice of 1 being the lowest and 5 being the highest desired for each question. I added all the scores for each response and did an average and then converted the score. my score average score was 4.38 which I converted to 88%. I was later informed by a colleague of mine that I should have use the following formula (Avg score-1)/4*100. When I did this calculation the score dropped to 85%. My colleague can't give me a clear explanation of why I should use this formula. Please advise

Answer 1

It's because 0 doesn't exist. 

 

This might make more sense if you write down the digits in order on paper and kind of get the visual.

 

You might also try this.  Make a line under it.  Be sure to start at the 1 and end at the 5.  Then divide the line into 4 sections.  You'll have 5 little slash marks, but 4 sections.  Then put 0% at the far left where the 1 is.  Put 100% at the right where the 5 is.  The 3 will be at 50%, the 2 is at 25% and the 4 is at 75%.

 

3/5 = .60

 

But is that where 3 is at on your line?

 

But (3-1) / 4 = .50 (50%)

 

It's a little weird.  I'm sure someone will want to give a really technical reasoning, but I really think the visual will help.  We're used to counting, and you aren't counting to 5.  (What if your choices were 2, 3, 6, 10 and 12?)