There is a .pdf summary here.
This is a 10 year chart of Average Sunday Attendance (ASA) reported by each geographical Diocese. The Dioceses are grouped regionally as Provinces. South Dakota is in Province 6.
You will see many negative numbers in the right column, which expresses the 10 year net.
For Province 6 (North Central USA), there were no net gains. North Dakota stayed even. The next best was Minnesota at -16%. The other Dioceses in the region all lost 20% or more over ten years, with Iowa and Colorado the worst at -24% each. South Dakota lost 22% of its ASA. The figure actually rose from 1998-99, to a high of over 2,900, but fell to just over 2,200 by 2008.
The chart employs an interesting statistical trick, apparently to mask the impact of the consecration of an LGBT bishop. The penultimate column breaks out percentage changes from 2003 - 2008. On first blush, this makes it look like declines actually slowed with acceptance of LGBT leadership in 2003. But if you go back to the annual columns, you will see that the big ASA drops, in most places, began in 2002, the run up to the General Convention that authorized the break with Christian Scripture, consensus and tradition. There were significant departures of those who saw the handwriting on the wall.
In South Dakota, 2002 ASA was over 2,800. It dropped sharply to 2,677 in '03, then began a more modest decline in the 2,500 range for three years before another large fall to the 2008 figure.
The 2009 statistics are available as bar charts at this site (enter name of Diocese, then name of parish to display - linking here does not work). South Dakota ASA appears to have decreased slightly from '08-'09.
Consistent with other diocesan reports, the SD 2009 graph shows an increase in financial giving. The increased giving reflects the generous efforts of remaining church people to try and keep things going, but this increased giving trend cannot long be sustained by a declining ASA.
The graph shows an increase in "membership," a vague number reflecting people on the church lists but not always active - as reflected in the disparity between membership and ASA. Many church development experts disregard "membership" numbers as unreliable.
The chart for my parish shows significant drop off in ASA and giving for 2009, after several years of growth. Denominational conflict contributed to this, as did family health problems that took a toll on my leadership. 2010 has stabilized and, in fact, is on pace for a record best budget year. This is due in part to the election of Bishop John Tarrant, who has invested time and energy in building a positive relationship with the parish.
Good to see St. Paul's, Brookings, gaining momentum with Fr. Ryan Hall.