RTPPM

PPM, the Public Performance Measure, is the percentage of trains that arrive 'on time' at their destination, regardless of who has impacted on the train service. Rather than simply focussing on trains arriving exactly on-time ('Right Time'), a reasonable tolerance is built in to the calculation.

• For long-distance services, 'on time' describes trains up to 10 minutes late
• For shorter distance services, 'on time' describes trains up to 5 minutes late

The PPM figures on the Open Data feed differs slightly from the official PPM figures issued by Network Rail:

• The RTPPM data calculates PPM on the basis on trains arriving at their destination between 0200 and 0159 the next day.
  • If a train starts its journey before midnight and finishes after 0200, it will not be counted in the day's figures.
  • If a train starts after midnight and finishes after 2am, it will be counted
  • If a train starts its journey before midnight but doesn't arrive at its destination until after 0159, it will not be counted
• All VSTP schedules are counted, i.e. trains that are planned or altered on the day they are due to run are included in the RTPPM figures, but would normally be excluded from the official PPM report
• Where a train has been cancelled prior to the day it runs, the RTPPM system will process that cancellation. If the train then actually runs, it will not be counted for PPM purposes, as the system would have already processed the planned cancellation and will treat the actual train as a duplicate
• Non-applicable trains are included in the RTPPM calculations, but not in the official PPM figures
• The system does not record 'fail to stop' events, diversions from the planned route or trains starting away from the planned origin. It does, however, count short terminations
• The system rounds down all percentage values to the nearest whole number, so 92.7% will be displayed as 92%
• The system cannot detect missed stops, which the official system picks up as a PPM failure through manual edits
• For Thameslink services, RTPPM only registers a PPM success or failure at the service's destination. This differs from the official system, which registers the services twice - once at Blackfriars (northbound) or Farringdon (southbound), and once at its destination

'CaSL' refers to Cancellations and Significant Lateness. The figure is made up by adding together the number of cancelled trains and the number of trains more than 29 minutes late. The percentage is derived from taking the total number of CaSL'd trains diving by the total number of trains due to run up until that point.

Message Topics

RTPPM messages are delivered through ActiveMQ.

Topic name	Description
RTPPM_ALL	Current realtime PPM statistics delivered once per minute

Record Layout

RTPPM records are encoded as a JSON hash with a key of "RTPPMDataMsgV1" and a value containing the RTPPM data, in the following layout:

RTPPMDataMsgV1:
 owner
 timestamp
 classification
 schemaLocation
 Sender:
  application
  organisation
 Publication:
  TopicID
 RTPPMData:
  snapshotTStamp
  SystemMsg
  RAGThresholds:
   <threshold values>
  WebPPMLink
  PPT:
   rag
   ragDisplayFlag
   text
  NationalPage:
   WebDisplayPeriod
   WebFixedMsg1
   WebFixedMsg2
   WebMsgOfMoment
   StaleFlag
   NationalPPM:
    Total
    OnTime
    Late
    CancelVeryLate
    PPM:
     rag
     ragDisplayFlag
     text
    RollingPPM:
     trendInd
     rag
     text
   Sector:
    <sector records>
   Operator:
    <operator records>
  OOCPage:
   WebDisplayPeriod
   WebFixedMsg1
   WebFixedMsg2
   Operator:
    <operator records>
  CommonOperatorPage:
   WebDisplayPeriod
   WebFixedMsg1
   WebFixedMsg2
  OperatorPage:
   <operator page records>

Field	Description
snapshotTStamp	The timestamp (in milliseconds since the UNIX epoch) when the report was created
WebDisplayPeriod	The maximum period of time (in seconds) the data should be displayed
WebFixedMsg1	Static message to show on a web page
WebFixedMsg2	Static message to show on a web page
Total	The total number of trains
OnTime	The number of trains on time
Late	The number of late trains
CancelVeryLate	the number of cancelled trains and the number of trains more than 29 minutes late
rag	G Good performance A Medium performance R Bad performance W Unknown
text	Current performance value (percentage)
trendInd	Trend Indicator + Rising trend = No change (flat) - Falling trend

Sector records

sectorDesc
sectorCode
SectorPPM:
 Total
 OnTime
 Late
 CancelVeryLate
 PPM:
  rag
  text
 RollingPPM:
  trendInd
  rag
  text

Field	Description
sectorDesc	Description of the sector
sectorCode	Code of the sector

Operator page records

Operator:
 code
 keySymbol
 name
 Total
 OnTime
 Late
 CancelVeryLate
 PPM:
  rag
  text
 RollingPPM:
  trendInd
  displayFlag
  rag
  text
OprToleranceTotal:
 timeband
 Total
 OnTime
 Late
 CancelVeryLate
OprServiceGrp:
 <operator service group records>

Field	Description
code	The sector code used to represent the TOC in TRUST.
keySymbol	The key character used to display different performance thresholds.
name	The name of the TOC.

Operator service group records

name
timeband
sectorCode
Total
OnTime
Late
CancelVeryLate

PPM:
 rag
 text
 
RollingPPM:
 trendInd
 displayFlag
 rag
 text

Field	Description
name	Name of the service group.
timeband
sectorCode	Code of the sector the service group is related to.