样本数据：
| Vendor | Size Group | Model | Quantity | Cost | TAT | Posting Date |
|--------|------------|-------|----------|-------|-----|-------------------|
| A | S | A150 | 150 | 450 | 67 | July 7, 2018 |
| A | M | A200 | 250 | 1500 | 75 | June 22, 2018 |
| A | M | A150 | 25 | 8500 | 85 | July 9, 2018 |
| C | L | A200 | 350 | 1250 | 125 | March 5, 2018 |
| C | XL | A500 | 150 | 6500 | 45 | February 20, 2018 |
| A | M | A900 | 385 | 475 | 40 | January 29, 2018 |
| A | M | A150 | 650 | 45 | 45 | August 31, 2018 |
| D | M | A150 | 65 | 7500 | 15 | April 10, 2018 |
| D | M | A300 | 140 | 3420 | 10 | April 3, 2018 |
| E | S | A150 | 20 | 10525 | 85 | January 3, 2018 |
| B | S | A150 | 30 | 10500 | 40 | June 3, 2018 |
| B | S | A150 | 450 | 450 | 64 | April 3, 2018 |
| E | XS | A900 | 45 | 75 | 60 | January 3, 2018 |
| F | M | A900 | 95 | 655 | 175 | January 3, 2018 |
| D | XL | A300 | 15 | 21500 | 25 | January 3, 2018 |
| D | S | A500 | 450 | 65 | 25 | May 3, 2018 |
| A | M | A350 | 250 | 450 | 22 | January 3, 2018 |
| B | S | A150 | 45 | 8500 | 28 | January 3, 2018 |
| A | S | A300 | 550 | 650 | 128 | January 3, 2018 |
| C | M | A150 | 1500 | 855 | 190 | January 3, 2018 |
| B | M | A150 | 65 | 1750 | 41 | January 3, 2018 |
| A | L | A500 | 75 | 1700 | 24 | January 3, 2018 |
| B | S | A900 | 55 | 9800 | 37 | May 29, 2018 |
| B | M | A500 | 150 | 850 | 83 | April 18, 2018 |
在提供的示例中，A和B的共同大小组均是S＆M。因此，我希望在群集柱形图中将这些大小组显示为图例，将平均成本显示为值。
有人可以建议我该怎么做吗？
谢谢！