Till early last week, it was showing 275 pages submitted and 274 pages indexed. From last 5-6 days, the number of pages indexed started decreasing. From 274 to 266 to 238, now it has come down to 225.
In fact, a 'site:' at Google shows all the results (about 275 pages) but the problem is that my Webmasters Tools says it has 275 submitted pages and only 225 indexed and I have no clue which pages have been deindexed.
I have 3 sites in my WMT and in all sites few pages are getting deindexed and they all started at the same time.
I have been running this website for last 4-5 years and never has any issue with it. Don't know where I am going wrong.