We know already that the operators choose their trigrams themselves and hence they show marked preference for some letters over others. On the left L and K are very good, Q and Y very bad. Also habits varied from place to place and we observed and allowed for them in creating a scoring system for each wheel divided into 3 geographical areas - N. Africa, Aegean and Black Sea. Here is a sample left hand wheel scorer, differences between areas were much more marked on the middle wheel though they are considerable here:
LEFT WHEEL
| N.Africa | Black Sea | Aegean | |
| A | +.9 | -1.0 | -3.8 |
| B | +1.9 | +3.1 | +3.2 |
| C | -5.7 | -2.2 | -1.5 |
| D | +1.0 | +.6 | +3.0 |
| E | -5.7 | -3.6 | -8.6 |
| F | +1.6 | +1.7 | +1.8 |
| G | +2.1 | +2.2 | -.4 |
| H | +3.5 | +3.3 | +2.9 |
| I | -1.7 | -6.9 | -4.9 |
| J | -4.8 | -4.4 | -9.2 |
| K | +4.0 | +4.5 | +4.5 |
| L | +7.0 | +4.1 | +4.1 |
| M | +5.6 | +1.7 | +2.5 |
| N | +1.9 | +.8 | +2.2 |
| O | -4.8 | -4.7 | -4.5 |
| P | -2.1 | -.3 | +1.4 |
| Q | -14.2 | -12.2 | -8.9 |
| R | +6.5 | +2.4 | +2.3 |
| S | +2.0 | +3.5 | +1.4 |
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