This is from Josh McDowell's book The New Evidence that Demands a Verdict pp. 199-200.
"The decree [of Artaxerxes to Nehemiah] was given in 444 B.C. based on the following: 1) 'In the month Nisan, in the twentieth year of King Artaxerxes' (Neh. 2:1); 2) Artaxerxes ' accession was in 465 B.C.; 3) There is no date specified, so according to the Jewish custom the date is understood as the first day of the month, which would be Nisan 1, 444 B.C.; 4) March 5, 444 B.C. is our corresponding calendar date."
It then quotes from a calculation made by Harold Hoehner in Chronological Aspects of the Life of Christ p. 138
"Multiplying the sixty-nine weeks by seven years for each week by 360 days gives a total of 173,880 days. The difference betweetn 444 B.C. and A.D. 33 then is 476 solar years. By multiplying 476 by 365.24219879 or by 365 days, 5 hours, 48 minutes, 45.975 seconds [there are 365 1/4 days in a year], one comes to 173,855 days, 6 hours, 52 minutes, 44 seconds or 173,855 days. This leaves only 25 days to be accounted for between 444 B.C. and A.D. 33. By adding the 25 days to March 5 (of 444 B.C.), one comes to March 30 (or A.D. 33) which was Nisan 10 in A.D. 33. This is the triumphal entry of Jesus into Jerusalem."
Of course I have my own questions about this, but it is an interesting take.