Peter, re: "it may be that there may be a need to push for other more frequent data sources using sampling methods rather than a full count and the long/short form." You might be interested in reading about the American Community Survey http://www.census.gov/acs/www/. It is slated to replace the long form (the short form will still be used decennially for reapportionment), and will produce annual and multi-year estimates, depending on geography. The upside is more frequent data, the downside is a smaller sample size. The ACS is concluding the planning/testing phases and the first national data will begin to be collected in 2003 for each county. Was this what you were asking for... Kendra Montanari Transportation Planner Middle Rio Grande Council of Governments -----Original Message----- From: Gardner, John F [mailto:GardnerJF@dot.state.sc.us] Sent: Wednesday, July 10, 2002 7:05 AM To: 'Peter J. Foote'; ctpp-news(a)chrispy.net Subject: RE: [CTPP] Reconciling Census Transit Commuters...Impact of Rail Lines etc Peter Foote's responses are excellent. Although I suspect the smaller metros have had such an increase in choice riders, because the congestion and parking cost incentives are not as strong. Very good point about the impact of prepaid fare media -- day passes, monthly passes, etc. -- boosting off-peak ridership. Prepaid fares help level the playing field between cars and transit. Drivers behave as if the marginal cost of an additonal trip or mile is zero; unlimited-ride passes induce the same behavior in transit users. -----Original Message----- From: Peter J. Foote [mailto:pfoote@transitchicago.com] Sent: Tuesday, July 09, 2002 8:34 PM To: Mark Schlappi; 'Chuck Purvis'; ctpp-news(a)chrispy.net Cc: dstuart(a)transitchicago.com; mpatzloff(a)transitchicago.com Subject: Re: [CTPP] Reconciling Census Transit Commuters...Impact of Rail Lines etc The impact of a new rail line, branch or extension on a system's unlinked trip count depends upon many factors. In general terms, the implementation of rail systems should generate new unlinked trips because they tend by nature to draw new customers, including suburban men, out of their cars. This is especially true when parking fees in the CBD are high. Links can be lost however, when rail route design allows former bus riders to save one or more transfers previously made on their commute. CTA's Orange line (running diagonally across the grid SW from the Chicago's Loop) which opened 10/31/93, was a bonanza for Pace suburban bus ridership for routes connecting to CTA at Midway airport. The line exceeded CTA ridership expectations in part due to high suburban ridership, but also resulted in some lost linked trips (not individuals) between bus routes - and of course a substantial shift from bus to rail. Limited stop express services can add individuals overall but eliminate the need for some transfers when they cross over route ends. The X49 for example, eliminated some transfers (unlinked trips) between routes 49A and 49, however ridership increases and customer satisfaction rose far more than trips lost. In Chicago, it is more likely that increases in off-peak discretionary riding by electronic pass users (30 and 7 day rolling pass markets have grown substantially since the were re-introduced in the Winter of 1998) are responsible for a portion of this shift. New York of course had tremendous ridership growth when the eliminated the 2nd fare required to move from bus to rail when their Metro Card was used. Check with them, but my guess would be that they have also had big boosts in off-peak riding, etc stimulated by having pre-paid media available. DC's Smart Card probably generates many new rides as well. Could the impact of just these 3 systems be enough to cause an increase in trips with no new net gain in riders? Once you have a farecard, even a money card rather than a pass, you are much more inclined to hop on a bus or train to take a trip. Discounting and the impact of lowered average fares on ridership through the use of these fare instruments may also be a factor. The issue of whether census data questions are complete enough to extract true mode splits (raised in another thread) is a valid one, especially when respondents are asked about an entire previous week is a valid one. BUT, I also think that it is unrealistic to expect more from the Census that can reasonably be expected. Reconfiguration of a rail line can cause losses. When the Dan Ryan/Lake and Howard/Englewood/Jackson Park were realigned 2/1993 to connect the busy South and North branches in the Red Line and less busy South and West branches as the Green Line many transfers which had been recorded as unlinked trips were eliminated with no real reduction in persons (average trip lengths expanded). Reconstruction of a rail line can also cause losses. The decision to close the Green line for reconstruction rather than single track in 1/1994 resulted in bus and offset gains made by the new Orange Line rail. The impacts of service changes are often complex. It likely that changes in auto ownership and transit riding frequency among fairly frequent customers over the decade are also an important of the story. It is also very difficult to make assessments of persons using a system from unlinked trip counts. This is part of why NTD average trip length calculations and passenger miles estimations are important. Peter J. Foote PFoote(a)TransitChicago.com Market Research/Resource Planning Planning Division Chicago Transit Authority 120 N. Racine Avenue Chicago, IL 60607 (312) 733-7000 x 6840 (Voice) (312) 432 - 7108 (Fax) **************************************************************************** **************************************************************************** ******************************************* Unless otherwise stated, the views expressed are those of the author and not those of the Chicago Transit Authority. **************************************************************************** **************************************************************************** ******************************************* http://www.TransitChicago.com CTA CUSTOMER SERVICE HOTLINE 1-888-YOUR-CTA RTA Travel Information 836-7000 ----- Original Message ----- From: "Mark Schlappi" <Schlappi(a)mag.maricopa.gov> To: "'Chuck Purvis'" <CPurvis(a)mtc.ca.gov>ov>; <ctpp-news(a)chrispy.net> Sent: Wednesday, July 03, 2002 6:01 PM Subject: RE: [CTPP] Reconciling Census Transit Commuters with Ridership Statistics have the (On 2000. APTA in transportation living" (in 40 which level, or the