Table 2. Selected characteristics of the study population.
| 2008 (n = 5,340) | 2009 (n = 5,321) | 2010 (n = 8,517) | 2011 (n = 8,558) | 2012 (n = 7,158) | 2013 (n = 7,178) | 2014 (n = 7,997) | 2015 (n = 6,141) | 2016 (n = 8,247) | 2017 (n = 7,245) | 2017 (n = 7,245) | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| % | % | % | % | % | % | % | % | % | % | % | |
| Age [mean (sd)] | 37.89 (8.82) |
38.05 (9.00) |
38.21 (8.99) |
38.25 (8.97) |
38.13 (8.79) |
38.16 (8.83) |
38.30 (8.85) |
38.45 (9.18) |
38.48 (8.69) |
38.20 (8.72) |
38.49 (8.79) |
| Gender | |||||||||||
| Man | 48.60% | 47.60% | 47.80% | 48.20% | 48.40% | 47.40% | 47.00% | 47.80% | 46.50% | 47.30% | 48.60% |
| Woman | 51.40% | 52.40% | 52.20% | 51.80% | 51.60% | 52.60% | 53.00% | 52.20% | 53.50% | 52.70% | 51.40% |
| Educational level | |||||||||||
| Less than HS | 25.70% | 23.60% | 42.40% | 38.20% | 37.00% | 33.60% | 34.40% | 34.40% | 40.00% | 32.70% | 30.10% |
| HS/ professional | 54.50% | 58.20% | 44.50% | 47.70% | 49.90% | 51.60% | 52.60% | 53.00% | 47.90% | 52.70% | 53.20% |
| College or higher | 19.80% | 18.10% | 13.10% | 14.10% | 13.10% | 14.80% | 13.10% | 12.60% | 12.00% | 14.60% | 16.60% |
| Missings | 0.10% | 0.20% | 0.10% | 0.20% | 0% | 0.20% | 0.10% | 0.20% | 0% | 2.60% | 0.10% |
| Income level* | |||||||||||
| Low | 26.90% | 26.90% | 23.20% | 14.40% | 14.60% | 26.00% | 14.00% | 19.40% | 14.40% | 13.00% | 23.50% |
| Medium-low | 35.80% | 38.50% | 44.00% | 39.10% | 37.20% | 40.10% | 34.60% | 30.30% | 34.10% | 31.60% | 32.40% |
| Medium-high | 25.90% | 25.00% | 23.70% | 30.50% | 34.30% | 22.00% | 32.80% | 34.10% | 35.50% | 37.20% | 30.30% |
| High | 11.40% | 9.70% | 9.10% | 16.10% | 13.90% | 11.90% | 18.60% | 16.30% | 15.90% | 18.30% | 13.80% |
| Missing | 39.10% | 50.60% | 62.10% | 57.80% | 49.60% | 45.30% | 39.90% | 47.90% | 37.80% | 46.60% | 47.80% |
| 69.81 (98.11) |
71.32 (104.92) |
86.33 (115.44) |
111.61 (118.15) |
147.90 (142.28) |
156.08 (146.11) |
||||||
| Missing | 48.63% | 49.60% | 37.96% | 38.06% | 43.94% | 29.15% | 0% | 0% | 0% | 0% | 0% |
| Bicycle use | |||||||||||
| No | 96.30% | 98.10% | 98.40% | 98.50% | 98.40% | 98.40% | 97.20% | 86.60% | 97.00% | 94.60% | 97.40% |
| Yes | 3.70% | 1.90% | 1.60% | 1.50% | 1.60% | 1.60% | 2.80% | 13.40% | 3.00% | 5.40% | 2.60% |
| missing | 1.90% | 1.00% | 1.00% | 1.80% | 1.70% | 1.00% | 0% | 0.70% | 4.60% | 0% | 0% |
SD, standard deviation; HS, high school.
*
For the surveys from 2008 to 2012 and 2014 the values were: low equivalent to ≤$200, medium-low equivalent to $201–$400, medium-high equivalent to $401–$800, and high equivalent to ≥$801. For the survey from 2013 the values were: low equivalent to ≤$100, medium-low equivalent to $101–$400, medium-high equivalent to $401–$800, and high equivalent to ≥$801. And for the surveys from 2015 to 2018 the values were: low equivalent to ≤$400, medium-low equivalent to $401–$800, medium-high equivalent to $801–$1,600, and high equivalent to ≥$1,601.