Extract giving wrong week of year

All,

                I’m seeing some odd behavior from the extract function.  Any idea why extract would think January 3^rd of next year is the 53^rd week of the year?

Thanks

Ben

[bprimrose@primrose partitioning]$ psql

Null display is "¤".

Line style is unicode.

Output format is wrapped.

Timing is on.

psql (9.3.9)

Type "help" for help.

bprimrose@home=> select extract (week from '2016-01-03 00:01:00'::timestamp);

date_part

───────────

        53

(1 row)

Time: 1.128 ms

bprimrose@home=> select version();

                                                   version                                                   

─────────────────────────────────────────────────────────────────────────────────────────────────────────────

PostgreSQL 9.3.9 on x86_64-redhat-linux-gnu, compiled by gcc (GCC) 4.9.2 20150212 (Red Hat 4.9.2-6), 64-bit

(1 row)