The average age of UK companies on the total register in 2018 to 2019 was 8.5 years, consistent with 2017 to 2018. Within both the total and effective registers for 2018 to 2019, over half of the companies were aged under five years (51.6% for the total register and 51.5% for the effective register). Over two-thirds (72.1% for the total register and 72.0% for the effective register) were under 10 years. Less than one in ten companies were aged over 20 years on both the total and effective registers. Chart 3: Age profile of companies on the total UK register for 2019 Historically, the average age of companies has always been relatively young, but it has gradually declined from 10.7 years in 2000 to 2001 to 8.5 years in 2018 to 2019. Between 2008 to 2009 and 2010 to 2011 the average age of companies fluctuated, corresponding with fluctuations in the numbers of incorporations and dissolutions, and declines in the overall register size. Since 2000 to 2001, the steady decline in the average age of companies could be due to the general increasing trend we have seen in the number of incorporations and dissolutions. It is likely that the increasing number of incorporations has led to a greater number of younger companies on the register, which has served to lower the average age of companies overall. The average age of dissolved and closed companies has declined from 5.7 years in 2012 to 2013 to 5.0 years in 2018 to 2019. Chart 4: Average age of companies on the total UK register from 2000 to 2019 Table A5, in the workbook that accompanies this release, shows the age profile of companies on the total and effective registers at 31 March 2019, as well as those in liquidation or the course of dissolution. The table also shows the average age of companies from 2000-01 to 2018-19. Table A11 shows the average age of dissolved and closed companies from 2012-13 to 2018-19, while Table C3 shows average ages at closure and dissolution across all corporate body types.