Table:
|  |  | Years Ended September 30, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
| Restructuring costs: |  |  |  |
| Cubic Transportation Systems | $  3.2 | $  0.4 | $  0.4 |
| Cubic Mission Solutions | — | 0.2 | — |
| Cubic Global Defense | 3.3 | 1.3 | 0.9 |
| Unallocated corporate expenses | 8.9 | 3.1 | 1.0 |
| Total restructuring costs | $  15.4 | $  5.0 | $  2.3 |
Paragraphs:
NOTE 19—RESTRUCTURING
In 2019, we initiated projects to restructure and modify our supply chain strategy, functional responsibilities, methods, capabilities, processes and rationalize suppliers with the goal of reducing ongoing costs and increasing the efficiencies of our worldwide procurement organization. The majority of the costs associated with these restructuring activities are related to consultants that we have engaged in connection with these efforts, and such costs have been recognized by our corporate entity. The total costs of this restructuring project are expected to exceed amounts incurred to date by $0.9 million and these efforts are expected to be completed early in fiscal 2020. Also, in fiscal 2019 our CTS and CGD segments incurred restructuring charges, consisting primarily of employee severance costs related to headcount reductions initiated to optimize our cost positions. The total costs of each of these restructuring plans initiated thus far are not expected to be significantly greater than the charges incurred to date.
Our fiscal 2018 restructuring activities related primarily to expenses incurred by our corporate entity to establish a North American shared services center. Our fiscal 2017 restructuring activities included corporate efforts to increase the centralization and efficiency of our manufacturing processes, as well as restructuring charges incurred by our CGD businesses related to the elimination of a level of management in the CGD simulator business.
Restructuring charges incurred by our business segments were as follows (in millions):
Question:
In which year was the restructuring costs incurred by Cubic Global Defense the lowest?
Answer: Because 0.9<1.3<3.3, the answer is: 2017.