Time series of overall CO specific emissions in ton TJ1
(1990-2006) for Australia, Japan, United States and EU152
are shown in Fig. 4 together with the corresponding value for the MABA for 2006. The MABA's overall CO specific emissions corresponded to the 1990 EU15 value, showing a 16-year lag in the incorporation of the European fleet technologies. A similar time lag of 10 years is observed with Australia and the United States.