Personalized subject lines in email marketing messages sent to promote Mother's Day gifts increase open rates by 54 percent and transaction rates by 66 percent, compared to emails without personalized subject lines, according to a report from Experian Marketing Services. The report also revealed that 46 percent of Mother's Day email volume is sent within a week of the holiday and that 75 percent of transactions and 80 percent of revenues for the holiday happen within two weeks of the holiday.