Forty-six percent of Mother's Day themed emails will be sent during the week before the holiday, according to data from Experian Marketing Services. It's not a big surprise, since Experian has found that 80 percent of transactions are triggered by emails sent in the 14 days before the holiday. Consumers like a good deal in these emails. According to Experian's data, there is a 32 percent transaction rate increase in emails that include an offer-based subject line. In addition, there is a 15 percent revenue increase for those emails.