Client has missing bills from 2018-2019. Avista says they only keep records for 2 years. How do you handle gaps in the data? Can't do a proper demand analysis without complete records.
Dealing with incomplete utility data
Check if the client has copies in their AP system or email archives. Florida Power & Light bills go to multiple people usually. I found 18 months of "missing" bills in the facilities manager's email.
Some utilities will provide older records for a fee. Tampa Electric charges $25 per year but gives detailed usage data. Worth it if you suspect a significant finding in that timeframe.
Use estimation methods for missing periods. If you have usage data but not billing details, apply the known rate schedule retroactively. Vectren in Indiana was helpful reconstructing bills from meter data.
Document the data gaps clearly in your report. State assumptions used for missing periods. Duke Energy in North Carolina accepted an audit with 4 months of estimated bills once I explained the methodology.
Check the utility's online portal. Sometimes bills are archived there longer than they keep paper copies. Inland Power in Washington had 5 years online when they said they only kept 2 years in files.
Third-party billing services sometimes keep longer records. If the utility uses a billing contractor, contact them directly. San Diego Gas & Electric uses a service that maintains 7-year archives.