Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Date | Event | Days | Stages | Acts |
| --- | --- | --- | --- | --- | --- |
| 1980.0 | 16 August | Monsters of Rock | 1 day | 1 stage | 8 bands |
| 1981.0 | 22 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
| 1982.0 | 21 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
| 1983.0 | 20 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
| 1984.0 | 18 August | Monsters of Rock | 1 day | 1 stage | 7 bands |
| 1985.0 | 17 August | ZZ Top: Rocking the Castle | 1 day | 1 stage | 6 bands |
| 1986.0 | 16 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
| 1987.0 | 22 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
| 1988.0 | 20 August | Monsters of Rock | 1 day | 1 stage | 6 bands |
Question:
Tell me the date for acts of 6 bands and year larger than 1981 for monsters of rock
Answer:
21 August, 20 August, 16 August, 22 August, 20 August