number of days between visits

[didierodayo]

Hello,

Dimension: ServiceDT

expressions:

7/(CERT_EXCLUDE_SERVICE_DT-Above(CERT_EXCLUDE_SERVICE_DT))

I need some help with period count. In the snapshot below I have a line chart with the expressions below. the chart works fine BUT now my requirement is

To work out the time between visits and show that number (days) on top of the line.

How can I achieve this please?

expected

Regards

Didier