Using criteria of bandwidth and energy consumption for signal guiding and processing, system-level figures of merit for both passive and active plasmonic circuit components are introduced, benchmarking their performance for the realisation of high-bandwidth optical data communication on a chip. The figure of merit for passive plasmonic interconnects has been derived in terms of the system level performance of the plasmonic circuitry, emphasising the bandwidth and power consumption densities. These parameters are linked to the local waveguide characteristics, such as the mode propagation length, bend radius and mode size. The figure of merit enables a comparison of the main types of plasmonic waveguides and can serve as a benchmark for future designs of photonic integrated circuits. A figure of merit for active photonic- or plasmonic-based electro-optical, thermo-optical and all-optical modulators is also derived to reflect the same benchmarking principles. A particular emphasis is made on establishing a practically oriented benchmark where the integral performance of the circuit, not the size or energy consumption of individual components, plays the defining role.