只需使用一个窗口函数：

SELECT YEAR(joined) AS JoinedYear,
       COUNT(*) AS Members,
       (-1 + COUNT(*) * 1.0 / LAG(COUNT(*)) OVER (ORDER BY YEAR(joined))) as growth_rate
FROM grp_member 
GROUP BY YEAR(joined) 
ORDER BY JoinedYear asc;

通过快速的web搜索，可以从sqlservercentral中发现以下示例：获取同比增长数据将您的基本查询作为cte，并对其进行自联接以获取上一年的值：

WITH Growth 
AS (
    SELECT YEAR(joined) AS JoinedYear, COUNT(member_id) AS Members
    FROM grp_member 
    GROUP BY YEAR(joined) 
    ORDER BY JoinedYear asc  
)
SELECT curYear.JoinedYear AS [Year], curYear.[Members]
FROM Growth curYear
LEFT JOIN Growth prevYear ON curYear.JoinedYear = prevYear.JoinedYear + 1
ORDER BY curYear.JoinedYear

在这里尝试：http://sqlfiddle.com/#!18/8a3f7/5型
年度会员同比增长20193020063202193
此输出中不包括成员总数，因为这应包括已失效或取消的成员的准备金，但这应是满足更复杂需求的简单入门。