The seventh volume of Card Captor Sakura ~Clear Card arc~ debutted at the 2nd position in Oricon’s weekly ranking, with an estimate of 98,089 copies sold in its first week of sales.
These numbers are for the regular edition, only. Numbers for the special edition (Drama CD part 1) are unknown as it did not appear on the ranking.
While these are the series’ 5th lowest first week (only topping first weeks of volumes 4 and 2, respectively, which were lower), I have a strong feeling that the main reason for that is that the special edition must have affected these numbers.
Volume 7 was up for pre-order many months prior to its release date so it is likely that the orders for the special edition were spread across the many weeks before the release date. That is, of course, just a personal guess.
It is worth mentioning that Oricon only takes into account a certain number of shops. These numbers are only an estimate and it’s possible that the real figures are higher than these.