A volume created for a dataset can be compared all over different datasets of the same site, in order to monitor its variations over time.
To compare volumes:
1. Select the volume tool by clicking 
in the 2D or 3D view and create the new volume or select a pre-existing volume.
2. On the right panel, click Compare volumes.
3. Select the time range for the volume comparison. Two options are available:
- The volumes of the defined area can be compared on all the datasets of the site.
- The volumes can be compared on a specific time window.
4. Define how the base surface elevation should be determined according to the points of the base polygon. By default, the triangulation method is used, but other options are possible. More information on which base surface is recommended to measure the volume in Which Base Surface is recommended for the Volume Calculation?.
5. Click Start. The results will start to be computed and they will be emailed to the project's owner in the form of a .csv file with quantified data.
this needs to be a controllable destination for the email / report to get sent to.
the whole point of BIM is that this is shareable data and needs to be accessible as a tool to ALL parties that have been shared the project.
At least enter an option for an email address to be entered to receive the report...
Hi thank you for your feedback,
I have passed it to our product owner for the future development of our products. Please notice that there is a dedicated section for feedback and suggestions on our Community https://community.pix4d.com/c/feature-request, where you can check which features have already been requested, upvote them adding a comment or post a new request.