Utility Meter +ve / -ve values

Hi thee, I’m brand new to HA and have just worked out how to use the Utility Meter and got that working properly counting the integration of my solar PV production. I would also like to use Utility Meter to monitor my grid import/export. Is it possible to tell Utility Meter to only aggregate positive or negative values? I only have a single sensor for import/export which goes negative when importing and positive when exporting. I would also like to use this to measure battery charge and discharge energy, again from a single sensor with +/- values.
Second question is where Utility Meter stores my daily values when it resets at the end of every day!
Thanks in advance.

Have you found a way? I would also be interested in doing this

me too, I need those negative values. statistics sensor works for last hour or so but not from midnight as I want