The desk reports 81.8%, which is 9 of 11 unique customers. Counting the same qualifying work over the three grains gives 81.8% over unique customers, 78.6% over sessions and 75.0% over tickets. The highest of the three reads 81.8% over unique customers, and the lowest reads 75.0% over tickets opened. A unit is counted as served once any one of its tickets qualifies, so which grain reads highest turns on whether the customers and sessions that came back more than once are the ones being served. The automated acknowledgement switch is not read here, because the numerator counts resolutions. Crediting work that finished after the window closed gives 81.8% against 72.7% for counting only what happened inside it. The 2 tickets that opened inside the window and finished after it are the whole argument. Across the 24 settings these switches can take, the same desk over this window reports anywhere from 56.3% to 100.0%, a spread of 43.8 points. The highest is tickets with any first response, automated ones included over unique customers, crediting work that finished after the window closed. The lowest is tickets with a human first response over tickets opened, crediting only what happened inside the window. Neither is dishonest and the desk did the same work in both. That spread is the argument an organisation has when the definition is not written down.