Hi all

I'm a stats newbie, and am working out the extent to which a product (say, ice cream) is selling to customers at a shop.

I have profiled all customers over the space of a year, and grouped them into sterotyped groups, also logging how many of these groups are purchasing ice creams on their visits to the shop

From this, I have worked out the index for each group to see how well each group is buying ice cream:

Rich & Famous - 123
Wannabe's - 130
Fairly Affluent Workers - 73
Traditional Folk - 52
Young and Trendy - 125
School Kids - 103
Not that well off - 52

Now I know that anything above 100 means that group is buying ice creams well, and below 100 means that ice creams do not appeal to that group.

But can anyone help me understand exactly what the figures mean? If an index is 123, does that mean the ice creams are selling 23% better to this group?

I can seem to get my head around translating indices into real world meanings...

Thanks all, any help is appreciated!!