There are no rewards for storing less than 1 GB for the month.
However, if a user has telemetry reports, exchange reports, or downloads they may still receive a reward.
There are no rewards if a user has not been seen in the past week.
Details
Each component (gbHours, telemetry reports, and downloaded bytes) is scaled so that each metric ends up being a measurement of how far away you are from the mean
Those values are multiplied by certain weights and summed to arrive at a final value
@cryptochrism: log on to https://community.storj.io/ and you'll find the spreadsheet in the #payments channel.