Bestseller List - Ranking Oddities

[morepork]

Hi everyone,

Is anyone else noticing oddities in the way Prestashop is displaying the ranking of bestselling products? Products listed in the Statistics area in order of number sold display differently in the Bestseller list - with some very distinct anomalies. Here is a list of products, their ranking by how many have sold as listed in the admin statistics area, and their corresponding ranking on the bestseller block and bestseller page on the site itself (I have the page configured to displaying in descending order, most sold first)

1) PRODUCT A - sold 65 - bestseller#2
2) PRODUCT B - sold 59 - bestseller#1
3) PRODUCT C - sold 51 - bestseller#3
4) PRODUCT D - sold 48 - bestseller#4
5) PRODUCT E - sold 45 - bestseller#7
6) PRODUCT F - sold 43 - bestseller#12
7) PRODUCT G - sold 43 - bestseller#5
8) PRODUCT H - sold 40 - bestseller#10
9) PRODUCT I - sold 39 - bestseller#6
10) PRODUCT J - sold 39 - bestseller#13
11) PRODUCT K - sold 38 - bestseller#8
12) PRODUCT L - sold 37 - bestseller#21
13) PRODUCT M - sold 36 - bestseller#16
14) PRODUCT N - sold 36 - bestseller#17
15) PRODUCT O - sold 35 - bestseller#11
16) PRODUCT P - sold 34 - bestseller#9


...and so on...

The product showing at the #2 ranking having sold 65, for example, should be number one. A customer purchased 15 of this item last week boosting its status as the bestseller and when I checked the order, that product was displaying correctly at number 1 ranking on the site. A short time later it had devolved to number 2. The only thing I can think of that changed in that time is I had marked the order to Preparation in Progress. Now it is Shipped and the ranking is still incorrect. But I'm not sure that has anything to do with it.

All the other oddities' statuses are set to Delivered. The current stock levels of those products vary (I have my store configured to allow ordering of products that are 'out of stock')

Any ideas?