I applied for B1 visa and after VO interviewed, he asked me to visit another counter. In this counter, an Indian female took details like height, sibling details, name of countries visited. She took my original passport and client invite letter and handed over a pink slip (221 g) with case number.

Can anybody tell me what does this case number designates? (It looks like 9999999 999 9)

I was able to find that first 4 numbers designate year, next 3 numbers designate nth day of the year. I am still unable to find what last 4 numbers designate. Can anybody explain what last 4 numbers means?

Daily I am checking my visa status, it is showing Pending process.

Thanks in advance.