Select Enable Custom Time Range to create a unique time range, trend time, resolution and label for the range. This appears in the Time Range list on the Application Health Status report when you enable it.
Hm.....How about custom time range? (Something like data for the interval in between 7 days ago and 4 days ago)
Or I can just have something like last 4 days or last 7 days?
@Wai Keat C., you should be able to configure any time range you want. Sometimes you can choose some time range which did not have any data, but at least, you can try any configuration.
You can go to the 3 dots menu on upper-right > edit report > time > time control type.
I guess the default is "none". If you use the DCRUM 12.4, you can change to "standard".
If you already use the 2017 version, you have other options, but the effect should be the same.