Back in August, I wondered if the credit card companies might be getting their groove back because it seemed like after a precipitous fall-off, the number of solicitations they send to our mailboxes was beginning to level off. Well, I was wrong, and credit card mail volume, as tracked by the research firm Synovate, resumed its slide. Until now. Here is the graph of the latest data. Mail volume is in millions. (Click on the chart to make it larger.)