1. Calculating MAP-21 Performance Measures Using NPMRDS Data
Chris Upchurch
Wichita Area Metropolitan
Planning Organization
This is really the third in a trilogy. Two years ago in Las Vegas I talked about using the NPMRDS data for some of our local performance measures. Last year I talked about the MAP-21 performance measures in the proposed rule. This year we have a final rule. Some of these measures have changed significantly, and the NPMRDS has changed significantly with a new vendor so I thought it would be worthwhile to revisit the topic a third time.

2. MAP-21 System Performance Measures Using NPMRDS Data
Level of Travel Time Reliability
Interstate
Non-Interstate NHS
Truck Travel Time Reliability
Peak Hours of Excessive Delay per capita
Earlier this year FHWA released a final rule for the System Performance measures. Three of them use the NPMRDS data.

3. MAP-21 System Performance Measures Using NPMRDS Data
Level of Travel Time Reliability
Interstate
Non-Interstate NHS
Truck Travel Time Reliability
Peak Hours of Excessive Delay per capita
I’m only going to talk about the Level of Travel Time Reliability and Truck Travel Time Reliability.
The Wichita region is not a non-attainment area, so I haven't really delved into Peak Hours of Excessive Delay.

4. MAP-21 System Performance Measures
How many of you plan to calculate these yourselves?

5. MAP-21 System Performance Measures
How many of you plan to calculate these yourselves?
How many plan to hire a consultant or use off-the-shelf software?

6. MAP-21 System Performance Measures
How many of you plan to calculate these yourselves?
How many plan to hire a consultant or buy off-the-shelf software?
How many haven’t made a decision?
I'm hoping that what I have to say will be useful to all three groups.

7. What is NPMRDS? National Performance Management Research Data Set
All of these measures rely on the National Performance Management Research Data Set or NPMRDS

8. What is NPMRDS? Travel time data for road segments Travel time data
5 minute time increments
Covers the National Highway System
Based on cellphone apps and in-vehicle navigation systems
Travel time data
Passenger vehicles
Trucks
All vehicles

9. What is NPMRDS
Since February 2017 the NPMRDS data has been provided by the University of Maryland CATT Lab
Data from INRIX
Texas A&M Transportation Institute
KMJ Consulting
They have been more responsive than the previous NPMRDS vendor.

10. How many have downloaded NPMRDS data and looked at it?

11. How many of you have done something with NPMRDS data?

12. Tools for Calculating MAP-21 Performance Measures
RITIS

13. NPMRDS Network
“In theory there is no difference between theory and practice”

14. NPMRDS Network
“In theory there is no difference between theory and practice, in practice there is.” – Yogi Berra

15. NPMRDS Network
In theory:
NPMRDS = NHS
In practice
NPMRDS ≠ NHS

16. NPMRDS Network
Cross streets

17. NPMRDS Network
Cross streets
Ramps

18. Downloading the NPMRDS Data
Massive Data Downloader

19. Downloading the NPRMDS Data
RITIS Provides a lot of options for customizing your dataset when you download
Customize your download or process the data after downloading?

20. Downloading the NPRMDS Data Geography
By State or County
Manual selection on map
List of TMC codes
Can save these for future reference

21. Downloading the NPRMDS Data Geography
Create a download for all the relevant counties
Download the GIS shapefile
Edit the shapefile until I have only the TMCs I actually want
Repeat for each network we’re interested in
Interstate
Non-Interstate NHS
Use that list of TMCs to download the NPMRDS data

22. Downloading the NPMRDS Data Day of Week/Time of Day
The final rule has 5 time periods
Morning: 6am to 10am (weekdays)
Midday: 10am to 4pm (weekdays)
Afternoon: 4pm to 8pm (weekdays)
Weekends: 6am to 8pm (weekends)
Overnight: 8pm to 6am (all days of the week, freight measure only)

23. Downloading the NPMRDS Data Day of Week/Time of Day
Can choose to download for any combination of days of the week or times of day
You can just download the data in one of those time periods, but it’s not limited to the time periods defined in the rule.

24. Downloading the NPMRDS Data Day of Week/Time of Day
Download 24/7 data and process later

25. Downloading the NPMRDS Data Type of Vehicle
Passenger vehicles
Trucks
Trucks and Passenger vehicles
None of the MAP-21 performance measures actually use travel times for just passenger vehicles, but it’s available.

26. Downloading the NPMRDS Data Type of Vehicle
Passenger vehicles
Trucks
Trucks and Passenger vehicles

27. Downloading the NPMRDS Data Units of Time
Minutes (to two decimal places)
Seconds

28. Downloading the NPMRDS Data Units of Time
Minutes (to two decimal places)
Seconds

29. Downloading the NPMRDS Data Time Interval
5 minutes (“Don’t Average”)
10 minutes
15 minutes
1 hour

30. Downloading the NPMRDS Data Time Interval
5 minutes (“Don’t Average”)
10 minutes
15 minutes
1 hour

31. Tools for NPMRDS
This is what it looks like when Excel breaks down and cries.
The file is too big for Excel to open.
For Kansas each month's file is about a gigabyte
Excel will show you the first few thousand rows.

32. Tools for NPMRDS Statistical Tools Databases Custom software
So you need some sort of specialized tool.

33. Level of Travel Time Reliability Metric
For each TMC segment and time of day
Divide:
80th Percentile Travel Time
50th Percentile Travel Time
If a segment has a ratio of <1.5 for all time intervals it is considered reliable

34. Level of Travel Time Reliability Measure
Sum for all reliable segments: Segment Length x Annual Volume x Occupancy Factor divided by Sum for all segments: Segment Length x Annual Volume x Occupancy Factor x 100
FHWA has not come out with occupancy factors yet. For the moment I am assuming that the occupancy factor in Wichita is one, which is pretty close to correct. If you are using one occupancy factor for your entire planning area it comes out in the wash anyway.

35. Truck Travel Time Reliability Metric
For each TMC segment and time of day
Divide:
95th Percentile Truck Travel Time
50th Percentile Truck Travel Time
Remember we have one more time interval than we do for the LOTTR metric

36. Truck Travel Time Reliability Measure
Total segment length x TTTR of the highest time interval divided by Total length of all segments
FHWA has not come out with occupancy factors yet. For the moment I am assuming that the occupancy factor in Wichita is one, which is probably close to correct. If you are using one occupancy factor for your entire planning area it comes out in the wash anyway.

37. Summary Calculating these measures yourself gives you more control.
RITIS download options can help make the calculations easier.
Still need some sort of specialized software.

38. Thank You

39. Questions?