tokens: between sunspot numbers and flare occurrence as a function of the solar cycle has been extensively examined, revealing a surge of renewed solar activity occurs a few years after the cycle maximum ( Fritzová-Švestková Švestka 1973 ; Švestka 1995 ). In a correlation analysis of flare occurrence and sunspot number, Temmer et al. (2003) noticed that the flare occurrence lags behind the sunspot number. For solar cycle 23, Bai (2006) found high flare activity in the late declining phase of the cycle. Not only was an increased flare activity noted but many low-latitude coronal holes were repeatedly observed during the declining and minimum phases of solar cycle 23 ( Abramenko et al. 2010 ). In addition, Gopalswamy et al. (2003) determined that the occurrence rate of coronal mass ejections (CMEs) peaked two years after the cycle maximum, and in the analysis of Kilcik et al. (2011) , the maximum speeds of CMEs also peaked approximately at that time. Recently, Lee et al. (2016) reported that the occurrence rates of major flares and front-side halo CMEs are higher during the descending phase of solar cycle 23 as compared to other phases of the cycle. The recent rejuvenation in the Sun’s large-scale magnetic field during solar cycle 24 starting in the second half of 2014, was pointed out by Sheeley Wang (2015) . They concluded that this was the result of systematic flux emergence in active regions, whose longitudinal distribution greatly increased the Sun’s dipole moment. The role of horizontal shear flows in building up magnetic stress in flare-productive active regions was already noticed by Harvey Harvey (1976) . Horizontal shear flows are not only responsible for magnetic stress but are also drivers for magnetic reconnection ( Yurchyshyn et al. 2006 ). Yang et al. (2004) measured the horizontal flows in active region NOAA 10486 before an X10 flare and found shear flows with local correlation tracking (LCT; November Simon 1988 ) of up to 1.6 km s −1 along the polarity inversion line (PIL). These strong shear flows were correlated with white-light flare kernels in the optical range. Strong horizontal shear flows, which decrease with height in the atmosphere, were also observed by Deng et al. (2006) in the same active region. Based on photospheric flows and the flux around the PIL, Welsch et al. (2009) derived indicators for the occurrence of flares. Many case studies established crucial links between photospheric shear flows, build-up of free-energy in a stressed magnetic field topology, and major flares (e.g., Tan et al. 2009 ; Liu et al. 2010 ). More recently, Beauregard et al. (2012) and Wang et al. (2014) analyzed the horizontal flows in the active region NOAA 11158 in relation to an X2.2 flare. The photospheric signatures produced by this major flare were rather diminutive. On the other hand, during the impulsive phase shear flows around the PIL showed a sudden decrease and a change in the intrinsic rotation of the two main sunspots. Recently,
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