What’s the actual rail growth?

The Herald reports:

Hefty patronage growth on Auckland trains is making the city’s transport authority bullish about meeting the Government’s conditions for an early start on the $2.86 billion underground rail project.

“We think it’s highly realistic,” Auckland Transport chairman Lester Levy said yesterday of the organisation’s prospects of persuading the Government to let it start digging twin rail tunnels between Britomart and Mt Eden before 2020.

He was commenting on a report to his board of a 13.9 per cent increase in rail patronage for the year to June 30, to 11.4 million passenger trips.

That sounds like a big increase.

That was 1.4 million trips more than last year, when patronage fell in the wake of the 2011 Rugby World Cup, interrupting a steady upward trajectory since Britomart opened in 2003 handling 2.5 million passengers.

So 2011 and 2012 figures are skewed by the World Cup. So let’s go back to 2010. That was 10 million trips a year. This year it is 11.5 million trips a year. But how many is that in terms of annual commuters? Let’s assume 250 working days and two trips a day.

In 2010 that was 20,000 Aucklanders using rail daily and and in 2014 it is 23,000 Aucklanders using rail daily. That is growth of 750 Aucklanders a year. It is 15% growth over four years which is just under 4% a year.

To make the target of 20 million trips to bring the CRL forward, you need over 12% growth a year.

Personally I think it will be a good thing if they do achieve ongoing 12% growth, and the CRL does happen earlier rather than later. But I’m somewhat doubtful that you assume growth based on the change over one year only. Let’s see what happens in the next 12 months.