title: query average response time for the last 1 minute
body: <p>We use prometheus and eclipse microprofile.
  There's a timer metric on my endpoint, so I can see the following metrics in prometheus:
  count,meanRate,oneMinRate,fiveMinRate,fifteenMinRate,min,max,mean,stddev,p50,p** etc.</p>
  
  <p>So I'd like to get the average response time for my endpoint, but only for the last minute.
  As I experience, the mean metric is calculated from the starting time of the application, so that's not good for me.
  Can you tell me any good query from prometheus which results the requested data?
  (The final purpose is to visualize the graph in grafana, but always show values for the last minute's average.)
  Thanks</p>