Operating expenses
nm—not meaningful
Research and development expenses
Research and development expenses increased $15.8 million in the year ended March 31, 2018 compared to the year ended March 31, 2017, which was primarily attributable to increases in personnel-related costs of $10.1 million, information technology and facility costs of $2.3 million, professional services costs of $0.9 million, share-based compensation expense of $0.7 million, travel and other costs of $0.5 million and data center costs of $0.5 million.
Research and development expenses for the year ended March 31, 2018 as compared to the year ended March 31, 2017 were negatively impacted by approximately $0.5 million primarily as a result of the weakening of the U.S. dollar relative to the British pound.
Personnel-related cost increased primarily as a result of salaries and benefits associated with increased headcount throughout the year, information technology and facility costs increased primarily as a result of increased headcount, professional services costs increased primarily as a result of the use of research and development contractors and share-based compensation expense increased primarily as a result of share option grants since the prior year.
Sales and marketing expenses
Sales and marketing expenses increased $25.1 million in the year ended March 31, 2018 compared to the year ended March 31, 2017, which was primarily attributable to increases in personnel-related costs of $13.5 million, marketing costs of $4.7 million, information technology and facilities costs of $3.6 million, travel and other costs of $2.3 million and professional services of $0.8 million.
Sales and marketing expenses for the year ended March 31, 2018 as compared to the year ended March 31, 2017 were negatively impacted by approximately $1.4 million primarily as a result of the weakening of the U.S. dollar relative to the South African rand and British pound. Personnel-related costs increased primarily as a result of salaries and benefits associated with increased headcount. Information technology and facility costs and travel and other costs increased primarily as a result of increased headcount.
General and administrative expenses
General and administrative expenses increased $9.1 million in the year ended March 31, 2018 compared to the year ended March 31, 2017, which was primarily attributable to increases in personnel-related costs of $5.0 million, share-based compensation expense of $1.2 million, information technology and facilities costs of $1.0 million and professional services costs and material supplies of $0.6 million each.
General and administrative expenses for the year ended March 31, 2018 as compared to the year ended March 31, 2017 were negatively impacted by approximately $0.3 million primarily as a result of the weakening of the U.S. dollar against the British pound and South African rand. Personnel-related costs increased primarily as a result of salaries and benefits associated with increased headcount.
Share-based compensation expense increased primarily as a result of share option grants since the prior year. Information technology and facility and material supplies costs increased primarily as a result of increased headcount.
Restructuring and Impairment of long-lived assets
In the fourth quarter of fiscal 2018, upon the exit of our Watertown, Massachusetts corporate office space, we recorded a restructuring charge of $0.8 million for remaining non-cancelable rent and estimated operating expenses for the vacated premises, net of sublease rentals, and a non-cash impairment charge of $1.7 million primarily related to leasehold improvements.
Table:
 | Year ended March 31, |  | Period-to-period change | 
% Change  | 2018 | 2017 | Amount | % Change
 |  | (dollars in thousands) |  | 
Operating expenses:                 |  |  |  | 
Research and development | $38,373 | $22,593 | $15,780 | 70%
Sales and marketing | 121,246 | 96,154 | 25,092 | 26%
General and administrative | 36,989 | 27,875 | 9,114 | 33%
Impairment of long-lived assets   | 1,712 | — | 1,712 | nm 
Restructuring   | 832 | — | 832 | nm 
Total operating expenses  | $199,152 | $146,622 | $52,530 | 36%


Question: What was the average Sales and marketing expenses in 2017 and 2018?
Answer: 108700
Calculation: (121,246 + 96,154) / 2