This site gives a chart with the date of every State Of The Union, and whether it was written or oral. From what I see, Washington’s first SOTU was on 8 Jan 1790, and he gave another eleven months later, on 8 Dec 1790, putting two in the same calendar year. The tradition of giving it at the end of the year continued until 1932, with exactly one SOTU per year, usually in December.
Hoover’s last SOTU was on 6 Dec 1932, and FDR’s first was on 3 Jan 1934, slightly less than 13 months later. There was none in the calendar year 1933, but if we allow for rounding, it is still accurate to say that there’s been an uninterrupted exactly one per year.
The next anomaly is in 1953. Truman gave an SOTU on 7 Jan 1953, just before he left office. Eisenhower gave his first less than 4 weeks later, on 2 Feb 1953, shortly after taking office. This pattern was repeated in Jan 1961, with both Eisenhower and Kennedy giving SOTUs.
Since then, we’ve gone back to exactly one per year, at the beginning of the year, usually in January (i.e., at the end of each year in office). LBJ gave one on 14 Jan 1969, six days before leaving office. Ford’s last was on 12 Jan 1977, 8 days before leaving. Carter’s last was 16 Jan 1981, 4 days before.
Reagan’s first was in 1982, at the end of his first year. It seems that he declined to give one at the end of his eighth year, and the SOTU for 1989 was given on 9 Feb 1989 by GHW Bush at the beginning of his term. Similarly, Clinton gave his first on 17 Feb 1993, at the beginning of his term as well. And likewise, GW Bush gave one at the start of his term too, on 27 Feb 2001.
Whew! All that leads me to this:
Out most recent SOTU was on 23 Jan 2007. If Obama waits until next winter to give his first, that will put a good 23-24 months or so between them. I concede that the Constitution does not require it to be yearly (only “from time to time”), but still, it will be a gigantic break with tradition if he doesn’t give one soon.