Table 1 - Summary of Data Analysis Adopted for the 1990 and 1995 NPTS
Table 1 - Summary of Data Analysis Adopted for the 1990 and 1995 NPTS
| Description of constraints | 1990 | 1995 |
|---|---|---|
| Sample size-total trips | 159,832 | 381,388 |
| Reasons for dropping records | ||
| Invalid destination | 3,314 | 43 |
| Trip in miles >200 | 23,372 | 27,455 |
| Travel minutes >120 | 3,015 | 5,254 |
| Age >65 years | 9,210 | 35,399 |
| Age <18 years | 21,470 | 63,832 |
| Shop duration >420 | 707 | 70 |
| Total dropped | 61,088 | 132,053 |
| Subtotal at trip level (after records are dropped) | 98,744 | 249,335 |
| Subtotal at person level | 15,870 | 52,341 |
| Travel + durationminutes >1,440 | 7,652 | 656 |
| Travel + duration minutes <1,440 | 2,643 | 17,119 |
| Duration <0 | 654 | 2,237 |
| Total dropped | 10,949 | 20,012 |
| Net total at person level | 4,921 | 32,329 |