When a user tracks a manually-updated account (such as a mortgage or loan) and enters balance snapshots on a monthly basis, the Net Worth chart currently displays a sawtooth pattern – the balance dips on the day of the update, then appears to jump back up the following day. This is because the chart plots only the discrete monthly stamps rather than interpolating between them.

The request is to support true linear interpolation between manual balance snapshots so that the Net Worth chart shows a smooth, continuous curve over time. For example, a mortgage declining from $1.84M to $1.58M over several years would display as a gradual, consistent downward slope rather than a series of sharp monthly dips and spikes.

This would make historical net worth trend analysis much more accurate and meaningful for accounts that are updated manually on a regular schedule.