Reliable estimate of how many users block iFrames?

A research institute is relaunching its website on a university-hosted TYPO3 system and needs to embed an interactive map and staff directory via iframes.

A colleague worries that some visitors block iframes, while IT says the impacted group is likely very small.

The team wants evidence, analytics, or industry guidance on how common iframe blocking really is.

The answer will help decide whether to keep the lower-cost iframe approach or pay for a redesign, with tradeoffs in cost, accessibility, and user experience.