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lower volumes. The screenline results are summarized in Table 8. Locations with <br />counts so low that they are less than the evaluation criteria are shown as "NA." <br />All screenlines and the total of all screenlines are within acceptable standards. It <br />should be noted that not all crossings of a screenline had count volumes. <br />Therefore, there may be some variations that are not completely explained by <br />this table. It is felt that all screenlines are within acceptable ranges. <br />Table 8 <br />Screenline Analysis <br />No. NAME <br />Tot Vol <br />Tot Count <br />% Deviation <br />% Allow <br />1 <br />CleElum <br />128 <br />76 <br />68% <br />NA <br />2 <br />West of Ellensburg <br />69 <br />55 <br />25% <br />NA <br />3 <br />North of Ellensburg <br />116 <br />84 <br />38% <br />NA, <br />4 <br />West Ellensburg <br />3207 <br />2388 <br />34% <br />47% <br />5 <br />11 North Ellensburg <br />474 <br />442 <br />7% <br />70% <br />61 <br />South of Ellensburg <br />488 <br />451 <br />8% <br />69% <br />7 <br />Central Ellensburg <br />5041 <br />5522 <br />-9% <br />33% <br />8 <br />EW Central Ellensburg <br />3184 <br />2841 <br />12% <br />43% <br />9 <br />East of Ellensburg <br />577 <br />629 <br />-8% <br />67% <br />Total <br />13284 <br />12488 <br />6% <br />23% <br />Scattergram Analysis <br />Several analyses of scattergram plots showing the correlation between traffic <br />count observations and model volumes were conducted. Figures 6 and 7 show <br />comparisons for ALL traffic counts and counts on just Freeways, Ramps, and <br />Principal and Minor Arterials, respectively. Typical standards are usually <br />compared on roads classified as Principal Arterial and higher classifications. <br />More deviation is expected when analyzing lower classification facilities such as <br />collectors and local roads due to the variation in traffic count data and the lower <br />volumes. Both figures show link ground counts on the X axis and assigned <br />volumes on the Y axis. On the green 'goal' line the assignment volume is equal to <br />the ground count. The red linear 'regression' line shows the best straight line <br />estimate of the assignment volume for any count. The blue 'allowable' curves <br />show the maximum allowable errors according to the graph discussed from <br />NCHRP 255. In both graphs there is one significant outlier. This is the <br />westbound 1-90 on-ramp at Cascade/University Way. This is an older count and <br />Kittitas County, Washington Transportation Model - May 2009 Page 41 <br />