Transaction Reports allow you to view your SMS transactions (that is, SMS sent and SMS purchased) for a particular period of time, so you can understand how you reached your account's SMS balance. You can view up to a 2 month period at a time.
The report works pretty much like a bank statement.
Each line represents a movement in your SMS balance, with a credit and debit column showing you how many SMS were transacted on that date. Any credits will also show the date when your credit is set to expire (3 months from date of purchase).
The last column will show your SMS balance to that date.
To access your account's transaction report, go to Reports > Transaction Reports.
Let's say you start off on 20 Feb with 118 SMS.
On 26 Feb, you sent 1 SMS (hence, it appears in the debit column), so your balance is now 117 SMS (118 - 1 = 117).
Then again, on 1 March you sent 3 SMS, so your new balance is 114 (117 - 3 = 114).
On the other hand, when you purchase SMS credit, it will show as a line in the credit column, bringing your SMS Balance up.
Any SMS you receive will NOT show up on your transaction report since they do not impact your SMS Balance.
Enter a start and end date, and the report will only display transactions in that time frame. Remember, you can only select up to a 3 month time period.