XF 1.4 Question re "Private Messages" in Forum Statistics

Hi, When looking at the tools area of our dashboard, at monthly statistics, I find that "Private Messages" is listed twice. When I click them both, I get two different summary bars - each with very different figures for "Private Messages."

Can someone tell me what each one is measuring?

I didn't, but now that I read your post, I can see that our developer did. I had originally asked him to change "conversations" to "private messages" in other places on the forum so our members, who were used to calling them private messages, from our previous PHPBB forum, would not be confused. Our members are dealing with the traumatic grief that follows suicide loss and are easily confused.

Thank you so much for clearing this up for me so quickly. I really appreciate it.