用一年的常数分母计算YTD和的运行平均值

Question

我有来自SQL

的下表

ID      Date         Score
-----+-------------+---------- 
10     2015-01-10      5
20     2015-01-10      5
10     2015-02-10      15
40     2015-02-10      25
30     2015-02-10      5
10     2015-03-10      15
10     2014-01-10      25
20     2014-02-10      35
50     2014-03-10      45

在Tableau中，我想要显示折线图 （年初至今得分总和）/一年的总ID数。

For Jan 2015 - 10/4=2.5
For Feb 2015 - 55/4=13.75
For Jan 2014 - 60/3=20

分母全年应保持不变，而不是按月变化。

Answer 1

Looks like you can achieve your desired result with two calculated fields. First, make a [Year] field with:

year([Date])

Then make a second calculated field as follows:

sum([Score])/sum({fixed [Year] : countd([Id])})

This will sum the score and divide by IDs for the given year. It uses Level of Detail计算。