Table 1. General properties of the 311 data for NYC, Chicago and Boston.
| Year | New York City | ||
| Total Requests | Requests Categories | Share of common categories’ activity | |
| 2012 | 1414392 | 165 | 0.69 |
| 2013 | 1431729 | 162 | 0.69 |
| 2014 | 1654913 | 179 | 0.73 |
| 2015 | 1806560 | 182 | 0.73 |
| Year | Chicago | ||
| Total Requests | Requests Types | Share of common categories’ activity | |
| 2012 | 478532 | 13 | 0.85 |
| 2013 | 507956 | 14 | 0.82 |
| 2014 | 515258 | 14 | 0.82 |
| 2015 | 568576 | 12 | 0.9 |
| Year | Boston | ||
| Total Requests | Requests Types | Share of common categories’ activity | |
| 2012 | 92855 | 155 | 1 |
| 2013 | 112727 | 165 | 0.99 |
| 2014 | 112785 | 183 | 0.96 |
| 2015 | 161498 | 180 | 0.83 |