I wrote recently about Kibana’s excellent Timelion feature, which brings time-series visualisations to Kibana. In the comments Ben Huang asked: do you know how to show whats the difference between this Friday and last Friday by Timelion? So I thought I’d answer properly here. Timelion includes mathematical functions including add and subtract, as well as the ability to show data offset by an amount of time. So to answer Ben’s query, we combine the two.