Can you see the number of log ins on your community in reports?

We are trying to look at reports to see whether our number of member log-ins will increase from a baseline taken this month, compared to the number of log ins in the future after we run a marketing campaign. We do not see the option to filter by # of log-ins on the community as an activity or form of participation. 

Has anyone else found a way to collect this information on user participation?

CC;