Based on a sample size of 163 million computers, 55% of all programs installed on personal computers running Windows are outdated according to an Avast report. Adobe Shockwave, VLC Media Player, and Skype among the most out-of-date Windows programs. 15% of Windows 7 users still use the OS’ Release to Manufacturing (RTM) version even though Microsoft closed its support window during 2013, with no major security updates being delivered since then for this build. Only educational users and businesses are receiving updates, all others should upgrade to the latest release, if possible.
Source: https://www.bleepingcomputer.com/news/security/outdated-software-exposes-pc-users-to-security-risks-says-report/