Robert - These records were compiled many years after the war, even well into the 20th century. One of the driving factors was the need to verify service for men (or their widows) who were applying for pensions. Looking through original documents every time a new pensioner had to be certified was both time consuming and likely to contribute to the wear and tear of those originals. The most common cards found in the records were derived from company muster rolls. Clerks in Washington would take original records, including said muster rolls, and make out a separate card for each man whose name appeared on the record. Muster rolls were made out every two months. So a typical card will state the soldiers name, rank, company, regiment, and for what time period it covers (Jan. - Feb. 1863, for example). Often his enlistment date and place is repeated on several cards. If the man was present on Feb. 28, 1863, the only notation on the card might be the word "Present." Other notations might include, "Sick in hospital", "Sick in camp (or quarters)", "On detached duty", "Captured at battle of XYZ", etc. In Confederate records it is rare to find a "complete" record covering every single 2-month period. Some are more complete than others. Other cards might include hospital records, POW records (these usually taken from Union provost marshal or prison records) or clothing issues, etc. As George mentioned, there are 21 cards in Dean's record. In my experience, this is probably a little above the average number in a typical Confederate soldier's record.