This paper analyses the productivity growth of the SUMA tax offices located in Spain evolved between
2004 and 2006 by using Malmquist Index based on Data Envelopment Analysis (DEA) models. It goes a
step forward by smoothed bootstrap procedure which improves the quality of the results by generalising
the samples, so that the conclusions obtained from them can be applied in order to increase productivity
levels. Additionally, the productivity effect is divided into two different components, efficiency and
technological change, with the objective of helping to clarify the role played by either the managers or
the level of technology in the final performance figures