As drearyweather says, this is an annual thing (possibly since 1984), and it usually appears around November.
The Box detailing ways to contribute is preceded by an article of varying length.
Watchtower November 2017: “The Generous Person Will Be Blessed”
Watchtower November 2016: "The Work Is Great"
Watchtower November 15, 2015: Show Appreciation for Jehovah’s Generosity
Watchtower December 15, 2014: Jehovah Richly Blesses a Willing Spirit
Watchtower November 15, 2013: How We Can Help to Meet the Needs of Others
Watchtower November 15, 2012: Their Surplus Offset a Deficiency
Watchtower November 15, 2011: Do You Find Joy in "the Privilege of Kindly Giving"?
Watchtower November 15, 2010: 'Let Us Present Jehovah's Offering'
Watchtower November 15, 2009: Cheerful Giving From the Heart
Watchtower November 15, 2008: Serving God With “One Heart and Soul"
Watchtower November 1, 2007: "The Silver Is Mine, and the Gold Is Mine"
Watchtower November 1, 2006: Unitedly Building to Praise God
Watchtower November 1, 2005: Contributions That Warm God's Heart
Watchtower November 1, 2004: Do You Know the Happiness That Comes From Giving?
Watchtower November 1, 2003: Cultivate a Giving Spirit