Can you actually keep your wait-time promise?
An average of five minutes can mean everyone waits five, or most wait three and one soul waits eleven. A histogram shows which support line you actually run, and the cumulative column turns it into a promise you can check.
Operations Starter Statistics free
After you install, this is the model to open.
What Shape Are Your Wait Times?
- In your spreadsheet, click the Sortia icon in the strip of icons down the right-hand edge. No strip? Click the arrow at the bottom-right to open it. You can also use Extensions, then Sortia, then Open Sortia.
- Click Start from a template and put that name in the search box.
- Pick the card with that name and click Load this template. It arrives on a new tab with real numbers already in it.
The answer
The distribution peaks in the four-to-six band and keeps a tail your average never mentions:
- Peak bin (4-6 min)
- 9 calls
- Answered within 6 min
- 70.8%
- Within 10 min
- 95.8%
- Beyond 10 min
- 1 call
The shape is the story: 70.8% of callers are done within six minutes, but one in twenty-four waited 11.5 minutes, and that caller is invisible in the 5.1-minute average and very visible on social media. Set bin limits that match the promise you make customers, paste your durations, and the cumulative column tells you whether the promise holds.
The model
Twenty-four support calls and their hold times, with bin limits at 2, 4, 6, 8 and 10 minutes typed in a second column. The tool counts each call into its bin and accumulates the percentages.
| Wait times (min) | 24 calls, 1.2 to 11.5 |
| Bin limits (min) | 2, 4, 6, 8, 10 |
| Count per bin | calculated |
| Cumulative % | calculated |
Once it is in your sheet
- The model arrives with real numbers in it and runs as it stands, so you can press the button first and understand it second.
- Change the numbers to yours. The sheet marks which cells are inputs and which hold formulas, and most labels carry a note explaining the row.
- Press the run button at the bottom of the panel. It is labeled for the tool you are in, and the result lands on its own tab, with a written reading of it beside the figures.
Never used Google Sheets? Start here goes the whole way, in seven steps, and assumes nothing.
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Every model like this one, and the method behind them: Statistics in Google Sheets.