pre_text: Cost of Revenues and Gross Margins Cost of revenues consists primarily of manufacturing materials, payroll, shipping and handling costs, manufacturing-related overhead and amortization of certain intangible assets. Our manufacturing operations rely on a limited number of suppliers to provide key components and materials for our products, some of which are a sole source. We order materials and supplies based on backlog and forecasted customer orders. Tooling and setup costs related to changing manufacturing lots at our suppliers are also included in the cost of revenues. We expense all warranty costs, inventory provisions and amortization of certain intangible assets as cost of revenues. Gross profit and gross margin by segment were as follows (dollars in thousands): Probe Cards Gross profit in the Probe Cards segment increased in fiscal 2019 compared to fiscal 2018 primarily due to increased sales, offset by higher variable costs and by less favorable product mix. Systems Gross profit and gross margin in the Systems segment increased in fiscal 2019 compared to fiscal 2018 due to increased sales. Corporate and Other Corporate and Other includes unallocated expenses relating to amortization of intangible assets, share-based compensation, restructuring charges, net, and acquisition-related costs, including charges related to inventory stepped up to fair value and other costs, which are not used in evaluating the results of, or in allocating resources to, our reportable segments. Overall Gross profit and gross margin fluctuate with revenue levels, product mix, selling prices, factory loading and material costs. For fiscal 2019 compared to fiscal 2018, gross profit increased due to increased sales while gross margins remained relatively consistent with fluctuations in product mix. Stock-based compensation expense included in gross profit for fiscal 2019 and 2018 was $4.1 million and $3.5 million, respectively.
table: Fiscal 2019
table: Probe Cards Systems Corporate and Other Total
table: Gross profit $211,382 $50,927 $(24,813) $237,496
table: Gross margin 43.0 % 51.9 % — % 40.3 %
table: Fiscal 2018
table: Probe Cards Systems Corporate and Other Total
table: Gross profit $187,320 $47,074 $(24,055) $210,339
table: Gross margin 43.1 % 49.3 % — % 39.7 %
table: Fiscal 2017
table: Probe Cards Systems Corporate and Other Total
table: Gross profit $195,903 $46,647 $(26,953) $215,597
table: Gross margin 43.1 % 49.8 % — % 39.3 %
question: Analyse this data from a financial earnings document. What is the increase/ (decrease) in Gross profit of Probe Cards from fiscal 2019 to 2018?