This issue has now been resolved. We apologise for any inconvenience caused.

We’re aware of a display issue for Composite Index Breakdown web pages on BitMEX.com and instrument/compositeIndex REST API endpoint. The trading engine is not impacted and all client funds remain safe. We’re investigating this and will provide a further update as soon as possible. We apologise for any inconvenience this may be causing. Please contact Support if you have any further queries.