mysql> select DAYOFYEAR('1979-06-11');
+-------------------------+
| DAYOFYEAR('1979-06-11') |
+-------------------------+
|                     162 | 
+-------------------------+
1 row in set (0.00 sec)

mysql> select DAYOFYEAR('1980-06-11');
+-------------------------+
| DAYOFYEAR('1980-06-11') |
+-------------------------+
|                     163 | 
+-------------------------+
1 row in set (0.00 sec)

mysql> select DAYOFYEAR('1981-06-11');
+-------------------------+
| DAYOFYEAR('1981-06-11') |
+-------------------------+
|                     162 | 
+-------------------------+
1 row in set (0.00 sec)