"'He will confirm a covenant with many for one "seven." In the middle of the "seven" he will put an end to sacrifice and offering. And on a wing of the temple he will set up an abomination that causes desolation, until the end that is decreed is poured out on him.'" NIV translation
Gabriel continues by explaining the second division of the 70 "sevens" which is the time of Great Tribulation as described by John beginning with Revelation 6. The "he" speaks of the antichrist and the unholy trinity (see Revelation 13).
Although the Jewish people have had more trials and troubles than any group of people on the earth, this period of "Great Tribulation" has not even begun yet.
There have been many attempts to mathematically explain when the last division of the "seventy sevens" (the start of the Millennial Reign) will occur. The attempts are futile as Jesus said that even He did not know when that would be. So, why all of the confusion? The simple fact of the matter is the period of time that is not described in the "seventy weeks" which is commonly called the Time of the Gentiles or Time of Grace. It is not counted in the "seventy sevens" because it does not apply to the Jews. We are currently between the 69th and 70th "sevens" and holding because of the grace of God.