As of 31 December 2015

  2015.12 2014.12 2013.12 2012.12 2011.12 Unit
Net sales 170.898 153,065 138,136 117,609 123,456 Yen (M)
Operating income 19,372 17,214 13,733 11,751 14,906 Yen (M)
Net income 12,882 10,589 8,999 7,396 8,664 Yen (M)
Total assets 231,032 207,335 189,269 153,836 144,649 Yen (M)
Total Net Assets 130,050 124,314 114,545 99,536 90,460 Yen (M)
Net income per share 305.73 250.28 212.76 174.87 204.88 Yen
Net Assets per Share 3,078.40 2,928.82 2,699.88 2,346.45 2,133.44 Yen
Cash dividends per share 70.00 67.00 60.00 50.00 40.00 Yen
Operating income to net sales 11.3 11.2 9.9 10.0 12.1 %
Net income to net sales 7.5 6.9 6.5 6.3 7.0 %
Return on shareholder's equity (ROE) 10.2 8.9 8.4 7.8 9.9 %
Shareholder's equity to total assets 56.1 59.8 60.3 64.5 62.4 %
Total shareholder return ratio 30.6 26.8 28.2 - - %
Dividend payout ratio (consolidated) 22.9 26.8 28.2 - - %
Dividend payout ratio (nonconsolidated) - - - 37.5 30.5 %
R&D expenditure 12,341 11,986 10,774 10,092 10,060 Yen (M)
Number of employees 6,831 5,965 5,787 5,530 5,448 Persons

Note: Since 2013, we have changed from dividend policy targeting at 30% of nonconsolidated net income to the total shareholder return, combined with the amount of dividend payments and share buybacks, targeting at 30% of consolidated net income. In fiscal 2012, we paid an annual dividend of 50 yen per share, including the commemorative dividend of 10 yen.