We have outstanding share-based awards granted to employees under the 2013 Equity Incentive Plan ("2013 Plan") and the 2017 Equity Incentive Plan (the "2017 Plan).  These plans permit grants of restricted stock, restricted stock units, performance stock, performance units, stock appreciation rights, stock options, as well as other share-based awards to eligible employees.  The 2013 Plan and the 2017 Plan also permit cash awards to eligible employees.  The 2017 Plan became effective May 2017.  No further grants of awards will be made under the the 2013 Plan, although awards under this prior plan remain outstanding.

We also have outstanding deferred stock units granted to directors under the 2017 Plan. Share-based awards were previously granted to directors and remain outstanding under the Non-Employee Director's Equity Plan and the Directors’ Stock Accumulation Plan, which has expired.

Compensation expenses are classified as selling, general and administrative expenses in the condensed consolidated statements of operations. Compensation expenses for the share-based awards were as follows:

In 2018, 2017 and 2016, we granted performance-based stock options that have a service condition as well as a market condition. In addition, some of the awards granted in 2016 contain a non-financial performance condition. We measure the fair value of these performance-based options at the grant date using a Monte Carlo simulation model.

Prior to 2018, we granted time-based stock options that contain only a service condition. We measured the fair value of these time-based options at the grant date using a Black-Scholes-Merton option pricing model.

We granted RSUs that contain only a service condition. We measure the fair value of RSUs based on the price of Brink’s stock at the grant date, adjusted for a discount for dividends not received or accrued during the vesting period.

Prior to 2016, we granted PSUs that contained a performance condition, a market condition and a service condition ("Prior PSUs"). After 2015, we granted Internal Metric PSUs ("IM PSUs") and Total Shareholder Return PSUs ("TSR PSUs").

IM PSUs contain a performance condition as well as a service condition. We measure the fair value of these PSUs based on the price of Brink’s stock at the grant date, adjusted for a discount for dividends not received or accrued during the vesting period. For the majority of the IM PSUs granted in 2018, the performance period is from January 1, 2018 to December 31, 2020.

TSR PSUs contain a market condition as well as a service condition. We measure the fair value of PSUs containing a market condition at the grant date using a Monte Carlo simulation model.  For the TSR PSUs granted in 2018, the performance period is from January 1, 2018 to December 31, 2020.

Prior to 2016, we granted MSUs that contained a market condition as well as a service condition. We measured the fair value of MSUs using a Monte Carlo simulation model.

We granted DSUs to our independent directors. We measure the fair value of DSUs at the grant date, based on the price of Brink's stock, adjusted for a discount for dividends not received or accrued during the vesting period.

Since 2015, our independent directors received grants of DSUs that vest and will be paid out in shares of Brink's stock on the first anniversary of the grant date, provided that the director has not elected to defer the distribution of shares until a later date. DSUs granted prior to 2015, in general, will be paid out in shares of stock following separation from service.