Besides the Shabats and the 7 appointed times (all timed from the beginning of the months, the New Moon), Yahuah included the observation of special years in a 7th year and 7x7 year cycles.
Sabbatical Year (Shmitta)
Leviticus 25:1-7, 20-22; Exodus 23:10-11; Deuteronomy 15:1-11 (release)
This is the seventh year, an "agricultural year," which is a year of rest for the land. It is also a time to relinquish (or forgive) debts, Deuteronomy 15:1-6, Jeremiah 34:13-14, Nehemiah 10:32.
On these years, the law was read to all during the Feast of Tabernacles, Deuteronomy 31:10-13.
The year starts after the Feast of Tabernacles, after the harvest is fully completed.
Generally, it was a year of sharing and "equalizing" for all will be planting from a similar start after the land has rested. This is a lesson to not rely on gathering material possessions (see Jubilee.
Sabbath years were likely observed in the years 135 BCE to 139 CE, including 28 CE, 69 CE
The Sabbath year occurred fall 69 to summer 70 according to the Sedar Olam. Rabbi Jose stated both temples were destroyed at the end of the Sabbath year.
Fall 1994 to summer 1995 was likely a Sabbath year. In the U.S.A., the summer of 1994 was one of the best producing years (thus likely a sixth year). The summer of 1995 had constant rainfall (or periods of little rainfall) that kept many farmers from working the field (per yaiy.org answers to appointed time).
Thus fall 2001 to summer 2002 would have been a Sabbath year based on what happened fall 1995 and projected from fall 69 to summer 70.
Next would be fall 2015 to summer 2016. Set Apart People have an analysis that points to 2016 also.
Daniel Gregg has the current fall 2013 to summer 2014 as a Sabbath year per page 207 (pdf) of his Scroll of Biblical Chronology and Prophecy.
In Luke 4:18-19, Yahusha quoted Isaiah 61:1-2, leaving off the reference to "the day of vengeance," which apparently refers to the "great and terrible day of Yahuah." Yahusha may come before (or on) the Sabbath year.