The following table sets forth the restructuring activity and balance of the restructuring liability accounts for the six months ended April 30, 2017 (in thousands):
| | | | | | | | | | | | | | Workforce reduction | | Consolidation of excess facilities | | Total | Balance at October 31, 2016 | $ | 868 |
| | $ | 1,970 |
| | $ | 2,838 |
| Additional liability recorded | 2,369 |
| (1) | 4,302 |
| (2) | 6,671 |
| Cash payments | (3,084 | ) | | (1,133 | ) | | (4,217 | ) | Balance at April 30, 2017 | $ | 153 |
| | $ | 5,139 |
| | $ | 5,292 |
| Current restructuring liabilities | $ | 153 |
| | $ | 4,928 |
| | $ | 5,081 |
| Non-current restructuring liabilities | $ | — |
| | $ | 211 |
| | $ | 211 |
|
| | (1) | Reflects a global workforce reduction of approximately 50 employees during the first quarter of fiscal 2017 as part of a business optimization strategy to improve gross margin, constrain operating expense and redesign certain business processes and systems. |
| | (2) | Reflects unfavorable lease commitments and relocation costs incurred during the second quarter of fiscal 2017 in connection with the facility transition from Ciena's existing research and development center located at Lab 10 on the former Nortel Carling Campus to a new campus facility in Ottawa, Canada. |
The following table sets forth the restructuring activity and balance of the restructuring liability accounts for the six months ended April 30, 2016 (in thousands):
| | | | | | | | | | | | | | Workforce reduction | | Consolidation of excess facilities | | Total | Balance at October 31, 2015 | $ | 591 |
| | $ | 688 |
| | $ | 1,279 |
| Additional liability recorded | 929 |
| | — |
| | 929 |
| Adjustment to previous estimates | — |
| | (10 | ) | | (10 | ) | Cash payments | (823 | ) | | (203 | ) | | (1,026 | ) | Balance at April 30, 2016 | $ | 697 |
| | $ | 475 |
| | $ | 1,172 |
| Current restructuring liabilities | $ | 697 |
| | $ | 309 |
| | $ | 1,006 |
| Non-current restructuring liabilities | $ | — |
| | $ | 166 |
| | $ | 166 |
|
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