Michael,
You could grab this data from the database - obviously making modifications to the database is something you would want to avoid, but you can get the raw data from the following tables in the report_db
nme_perf_v_origindata : Raw Data for each device, instance, performance task, at each polling interval. This is the data dump
Then you can use (all also in report_db)
plat_v_dev: correlate device ID with friendly device name, IP address, etc
nme_perf_v_task_inst: correlate the instance ID with friendly name (i.e. Instance ID 7 = CPU:.0)
nme_perf_v_task_temp: correlate the task_id with friendly tank_name (i.e. task_id 2 = CPU Usage)
You could use a fancy excel spreadsheet to pull the raw data, you wouldn't necessarily need the additional tables, those would just be handy if you wanted to translate the dev_ID, task_ID etc. In excel under the data tab you can create a link to the db tables and pull the data in.
Hope that helps,
PL