We store most of our numbers in the WMF graphite instance.
As has been mentioned many times if ops need to delete data to get graphite working again they might just do that. (see T85451)
For this reason we should periodically grab the key metrics that we care about and store them somewhere else (Could just be on labs, locally or some machine with some space)...
See https://github.com/wmde/graphite-backup for a script that does everything we need..
#!/bin/bash
php ~/graphite-backup/run.php daily.wikidata.api.wbgetclaims.properties.*
php ~/graphite-backup/run.php daily.wikidata.site_stats.user_groups.*
php ~/graphite-backup/run.php daily.wikidata.site_stats.*
php ~/graphite-backup/run.php daily.wikidata.social.email.*.subscribers
php ~/graphite-backup/run.php daily.wikidata.social.*.*
php ~/graphite-backup/run.php daily.wikidata.entity_usage.*.*
as a start