Punctuality development and delay explanation factors on Norwegian railways in the period 2005–2014

The paper revisits an investigation of delays and punctuality on Norwegian railroads from 2010, re-evaluating its findings and studying the effects of later measures put in place between 2010 and 2014. Norwegian railways saw a steady decline in punctuality from 2005–2010, prompting the establishment of a task force to understand the trends and patterns behind the delays on the network. Data was collected on punctuality and delays, as well as on factors that were likely causes of delays. The original study pointed to three main areas that cause delays during the period 2005–2009: (1) an increased error rate in infrastructure and rolling stock, (2) extensive work close to the tracks due to increased maintenance and renewals and (3) an inability to perform consistently even under normal weather conditions. Measures were put in place to turn around the overall performance. Appending data for 2010–2014, new regression models indicate that although their influence on delays and low punctuality changed as these measures have been put in place, some factors remained influential: low temperature ( 10 cm), reduced train lengths and increased volume of train services (both freight and passenger trains) still contribute to delays and low punctuality. The paper contributes to the literature on empirical analyses of delay causes. However, it can also be read as an illustration of an approach for an ex post evaluation of effects from punctuality improvement initiatives.