Measuring productivity

Today my bosses were all not around and I thought I could get a relaxing day in the office. It's rare that all the bosses are not around, but looking back on today, I think it's one of the more productive days in a while. Sent out a productive 21 work related emails today. Don't think I've sent so many emails in a while, the number the last few days have been in the low tens. Oh well, there'll be more days without bosses soon as they are all clearing leave these days. However, I think there is something inherently wrong when productivity can be measured by the number of emails sent...