The Open Data Portal of Sri Lanka (http://www.data.gov.lk) was established a few years ago, but to date, doesn’t seem to have much data.
Download the first archive of the site, with all datasets, taken on 11 June 2018, here.
The Department of Census and Statistics in Sri Lanka is a treasure trove of fiction, sorry statistics. This archive gives offline access to all the data on the site, including:
The archive also contains the comprehensive information on the damage caused by the December 2004 tsunami and the statistical abstract for 2007.
Click here to download the archive (116.4Mb).
Note that the site seems to have been done on Microsoft FrontPage 6.0 (gasp!) so though the fancy graphics and menus don’t load, the text links to all the content work just fine.
Eight years after the first archive, got around to archiving the site again. From 116Mb, the site is now closer to 2Gb in size, though compressed it is smaller.