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An alternative parameter $R_{J_z}$ is introduced as the ratio of one of twokinds of opposite-sign current to the total current and investigate therelationship between the quantity and the hemispheric sign rule of helicity(HSR) that is established by a series of previous statistical studies. Theclassification of current in each hemisphere is according to the followingrule: If the product of the current and the corresponding longitudinal fieldcomponent contributes a consistent sign with reference to the HSR, it is called"HSR-compliant" current, or else it is called "HSR-noncompliant" current.Firstly, the consistence between the butterfly diagram of the $R_{J_z}$ and thecurrent helicity was obtained in a statistical study. Active regions with$R_{J_z}$ smaller than 0.5 tend to obey the HSR whereas those with $R_{J_z}$greater than 0.5 tend to disobey the HSR. The "HSR-compliant" current systemshave 60\% probability of realization compared to 40\% of "HSR-noncompliant"current systems. Overall, the HSR is violated for active regions in which the"HSR-noncompliant" current is greater than the "HSR-compliant" current.Secondly, the $R_{J_z}$ parameter was subsequently used to study the evolutionof current systems in the case analyses of flare-productive active regions NOAAAR 11158 and 11283. It is found that there were "$R_{J_z}$-quasi-stationary"phase that is relatively flare quiescent and "$R_{J_z}$-dynamic" phase that iscovered by the occurrence of large flares.

A Quantity Characterising Variation of Observed Magnetic Twist of Solar Active Regions