I do, however, have an unofficial answer. I get this answer from the Bible and the Feast of Trumpets, also called Rosh Hashanah. It is the Jewish celebration of the New Year, except their New Year comes in September or October.
Two activities are designated by God in the Scriptures for this day (Leviticus 23:23-25; Numbers 29:1-6). I am sure other traditions have been added, but I only note these two activities. First of all, no regular work was to be done on that day. As one "ceased" for the Jewish Sabbath, so also one stopped for the Day of Trumpets, the new year. One emptied one's schedule of your normal day to day work. Sounds good to me, how about you?
Secondly, one filled one's schedule with at least some time of worshiping God. Worshiping God involve offering a burnt offering. A burnt offering represented surrendering one's whole life to God. One also offered a sin offering. One spent time searching one's heart and confessed one's sin to God. Thus, New Year's day involved worship of God. One surrendered one's life to him for the present and future new year, and one looked in the past and asked forgiveness from God. That sounds good also.
Did Jesus celebrate this way? I don't remember any specific reference to him doing so. I am sure he didn't follow all the Pharisaic traditions that may have been developed; he probably obeyed the spirit of the law - the rest and worship. Sounds like a good idea to me.