Traffic Speed Report No. 91

RSTR"CT T~i.r.portIs t~.annu.lcontinuln~.tudy of .pc.ds of vc~iclc.on rural indiana lIi~h".ys.O~.orv. .iono of .pot.peed.w.re toten on int... U'e, four•l.ne,and holane ~I~hwoys t~roul~ou, 'he .. ate duTing 'he .ontho of June .nd"ugu.t197~."nalph of ,he .peed• • ho"ed ,~e o"eTOli , ... nge .peedfor puseng.rco.. "a> 6S.1.0all .. per hour.The o ... er.11 ....... g. 'p••d ror huvy tru,k." .. SB.B .il.. per hour.Thl."05 thc .0.0 over.11.vcroge.pe.d for P....nBer c.co .ndI.Z .phaore for truck.t~"n .I.ilat data Biven for 1HZ ., ,h ••••e locations (exc.pt for "atlon 10 "hieh hxd been .hift.d to the orlalnll .Ite of ,h.pre ... iou • • tudi •• ).Sl.pl.linear rear •• slon analy.l.On ,h.d.t. of the put .le... en year • • ~o"ed In annual lncre..e of 0.62 aph for tbe e roll o oroge speed of pa .. engcc cars and O. H aph for the o roll & roBe speed of hUvy trock •.T~ese ,rend.u .10 .. ,~an t~at of a ton year period ending flve or .ixyear.&BO and appelr.to r.sult froa a "Ic,..ling-eff" of a.xl.ua .p.ed. in recen' year •.... .ihllouth .,