Performance has declined during the 2004-2009 time period.
Cf. SF Muni Metro Performance Graphs.

On-time performance Date J Church K Ingleside L Taraval M Oceanview N Judah Average or Total Jul-Dec 2004 80% 81% 76% 70% 79% 77% Jan-Jun 2005 57% 72% 79% 71% 69% 70% Jul-Dec 2005 54% 75% 87% 65% 83% 73% Jan-Jun 2006 70% 69% 64% 61% 69% 67% Jul-Dec 2006 61% 68% 72% 73% 73% 69% Jan-Mar 2007 71% 81% 71% 74% Apr-Jun 2007* 74% 72% 2004-2007 average 66% 74% 75% 69% 74% 72% standard deviation 9% 5% 7% 4% 5% 7% daily riders in thousands 19 15 23 23 31 112 scheduled time for route in minutes 44' 36' 35' 43' 38' 40' *The T line began service in April, 2007

Runs operating within scheduled headways Date J Church K Ingleside L Taraval M Oceanview N Judah Average or Total Jul-Dec 2004 62% 100% 90% 44% 50% 69% Jan-Jun 2005 55% 100% 100% 79% 41% 75% Jul-Dec 2005 37% 56% 82% 57% 60% 58% Jan-Jun 2006 49% 57% 41% 67% 58% 54% Jul-Dec 2006 37% 54% 52% 67% 62% 54% Jan-Mar 2007 42% 76% 61% 65% Apr-Jun 2007* 60% 88% 2004-2007 average 47% 74% 71% 63% 60% 63% standard deviation 9% 20% 21% 11% 14% 18% daily riders in thousands 19 15 23 23 31 112 scheduled time for route in minutes 44' 36' 35' 43' 38' 40'

On-time performance Date J Church K Ingleside -T Third L Taraval M Oceanview N Judah Average Jul-Dec 2007 67% 75% 79% 59% 69% 70% Jan-Jun 2008 n.a. 74% 70% 72% 65% 70% Jul-Dec 2008 62% 61% 70% 62% 73% 66% Jan-Jun 2009 72% 68% 73% 70% 68% 70% Jul-Dec 2009 72% 84% 73% 68% 78% 75% scheduled time for route in minutes* 35' 73' 36' 40' 47' 44' *The changes in time from 2004-7 are due to several changes in routes. The K and T lines are combined.

Runs operating within scheduled headways Date J Church K Ingleside -T Third L Taraval M Oceanview N Judah Average Jul-Dec 2007 74% 75% 66% 62% 50% 65% Jan-Jun 2008 n.a. 56% 53% 60% 46% 54% Jul-Dec 2008 42% 40% 50% 49% 53% 47% Jan-Jun 2009 53% 48% 54% 44% 35% 47% Jul-Dec 2009 49% 66% 58% 62% 47% 56% scheduled time for route in minutes* 35' 73' 36' 40' 47' 44' *The J ends at Embarcadero instead of 4th and King Streets. The N ends at 4th and King Streets rather than the Embarcadero.

Muni Metro performance is checked once every six months for every line.  Muni data since July, 2004, is posted quarterly at SFMTA, two to three months after the end of each quarter.  Ridership numbers are from sfgate.com.  511.org has Muni Metro schedules. The Muni goal is to have at least 85% of vehicles run on time according to published schedules, no more than 4 minutes late or 1 minute early. The Muni goal is to have at least 85% of vehicles within the lesser of 30% or 10 minutes of scheduled headway (interval between trains in minutes). Using linear regression, there has been a gradual decline in the average on-time percentage and headway for the Muni Metro system during the 2004-2008 time period.  Muni Metro performance graphs. Headway, the interval between trains, is more important to most passengers than the on-time performance.  Most passengers do not carry schedules and the schedules are not posted at Muni stops. If a train is scheduled to arrive every ten minutes, for example, and every train is five minutes late, the interval between trains would still be every ten minutes. The results for headway between trains are worse than those for on-time performance in the above data. This may be because the criteria for headway are stricter than the criteria for on-time performance in many cases. A train is not considered late unless it is at least four minutes behind schedule. As the scheduled headway during commute hours ranges from seven to ten minutes for the Metro system, a train that is two to three minutes late may not meet the criteria for headway. The FY2007Q4 performance data did not include any information about the T-Third line which was in service that quarter. An early report was that the trains showed up on schedule just 23 percent of the time. Combining the K-T lines in FY2008Q1 ended the turnaround of the T line at Castro Street.