请阅读下面这张Markdown格式的表格并回答问题。同一行中不同列的单元格用'|'分隔，不同行的单元格用'
'分隔。

表格标题:
43 表3：重点城市周均环比（单位：%） 
表格:
| 时间 | 北京 | 上海 | 广州 | 深圳 | 杭州 | 天津 | 南京 | 武汉 | 重庆 | 成都 | 青岛 | 苏州 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 2011/6/4 | -43.29 | -10.84 | -9.47 | -3.82 | -1.15 | 0.97 | -12.24 | 57.25 | 31.31 | -17.04 | -49.43 | -4.54 |
| 2011/6/11 | 59.57 | -29.0 | 24.33 | -34.13 | -14.57 | -19.17 | -37.48 | -8.09 | -39.2 | -33.55 | 28.14 | -31.93 |
| 2011/6/18 | 16.25 | 11.43 | -6.98 | 114.46 | -12.34 | 9.01 | 98.32 | 3.13 | 38.91 | 38.3 | 51.38 | -2.92 |
| 2011/6/25 | 6.23 | 26.4 | -32.84 | 45.08 | 7.88 | -4.88 | -22.73 | 22.77 | -1.83 | 21.27 | -11.3 | 23.58 |
| 2011/7/2 | 26.21 | 28.76 | 37.54 | -4.65 | 46.57 | 33.23 | 17.37 | 8.26 | 40.71 | 6.04 | 39.64 | 53.99 |
| 2011/7/9 | -18.4 | -34.17 | -36.04 | -10.66 | -37.74 | -11.47 | -12.67 | -32.47 | -17.7 | -26.85 | -12.11 | -49.56 |
| 2011/7/16 | 4.41 | 3.83 | 21.28 | -11.48 | -7.03 | -5.86 | -7.33 | -7.68 | -59.54 | 17.03 | -10.73 | 4.18 |
| 2011/7/23 | -2.57 | 19.26 | -5.82 | 8.34 | 1.17 | 10.04 | 57.33 | 13.51 | 22.42 | -1.98 | 9.46 | 16.39 |
| 2011/7/30 | 4.94 | 19.93 | -16.63 | 39.69 | 0.9 | 4.28 | -10.47 | 3.74 | 49.0 | -9.07 | -5.57 | -8.48 |
| 2011/8/6 | -55.25 | 3.15 | 60.89 | -14.33 | -4.47 | 7.97 | -21.52 | -2.27 | 4.94 | 69.66 | -7.0 | 98.9 |
| 2011/8/13 | 0.82 | -16.09 | -18.0 | -50.5 | -11.9 | -8.29 | -3.13 | -14.57 | -18.57 | -22.22 | -27.5 | 28.89 |
| 2011/8/20 | 33.02 | -5.25 | 8.21 | 22.4 | 0.91 | -1.41 | -17.23 | 14.17 | 18.01 | -25.52 | 34.83 | -7.96 |
| 2011/8/27 | -18.64 | -1.89 | 23.4 | 36.6 | 36.99 | -4.16 | -6.51 | 23.53 | -14.5 | -22.56 | -3.03 | -11.91 |
| 2011/9/3 | 15.63 | 11.09 | -23.17 | -21.41 | 14.49 | 11.9 | 10.54 | 13.97 | 28.37 | 24.24 | 36.77 | 58.61 |
| 2011/9/10 | -16.39 | 0.37 | 2.11 | 19.48 | -15.05 | -12.71 | 63.13 | -4.59 | 12.14 | 34.22 | -6.95 | -26.33 |
问题:
北京周均环比小于0并且上海也如此，这样的情况发生在什么时候
Answer:
2011/6/4
2011/7/9
2011/8/27