Counting records in WorldCat

How many records are in WorldCat?  The simple answer is just over 60 million, since the 60 millionth OCLC number was just added May 2nd (you can watch records go in here).  But of course, things aren't quite that simple.  According to Gary Smith here at OCLC, in the first week of May 2005, there were slightly more than two million cross reference records in WorldCat.  These are created when records get merged.  When you ask for a record that got merged into another record the cross reference record automatically refers you to the merged record.

There are also records that are missing completely.  The famous Apple Cake recipe, which has probably been deleted more than once from WorldCat, would be an example of that.  This month there are nearly 450,000 of those.  Taking both cross reference and missing records into account reduces the 60 million by some 4.4% to around 57.4 million bibliographic records.

At least as important as record count are the holdings associated with the records.  There are about 16 holdings/OCLC#, a statistic that has been relatively stable for decades.  When things are busy, nearly thirty holdings get added each second, although three per second is more typical.  Libraries often modify records while setting holdings, and we have copies of all those changed records, although we don't keep them online (yet).

This year (2005) WorldCat will pass 1,000,000,000 holdings.

--Th

Comments

[Ed Summers]

Hey that updating page is neat. I hacked a supybot plugin for our bot panizzi in #code4lib so you can say:

14:04 < edsu> panizzi: worldcat
14:04 < panizzi> edsu: [May 13, 2005 03:01 PM EDT #980,575,416] World Book's animals of the world. Ogden, Dennis. ... uploaded by CAU - CAPITAL UNIV LIBR

Friday fun.