First, regarding sector diversification, for example, if the holdings in a high dividend stock portfolio are 'Nippon Telegraph & Telephone Corp,' 'KDDI,' and 'SoftBank,' and all sectors are in the communication industry. In such a portfolio, if the communication industry as a whole falters or legal regulations are enacted, there is a possibility that all holdings may fall into poor performance and stock price declines. As a result, there is a possibility of reduction in dividends, where even 'the bird in hand (income gain)' may not be obtained. In reality, in the communication industry, due to the 'reduction of mobile phone fees' by the Suga Cabinet in 2021 and 'entry of Rakuten as a new communication carrier,' the stock prices of each company dropped significantly. Also, with the reduction in mobile phone fees, profit margins have deteriorated. To prevent such a situation, it is necessary to diversify into '5 or more sectors' when forming a high dividend stock portfolio. For example, in high dividend stocks in Japan, it would be advisable to divide the sectors into categories such as 'communications, A-REIT ETF, construction, industry-Industy, and retail.' Representative examples for each would be 'communications = Nippon Telegraph & Telephone Corp, SoftBank, KDDI,' 'construction = Sekisui House, Haseko Corporation,' 'industry = Itochu, Mitsubishi Corporation,' 'industry = Mitsubishi UFJ, Sumitomo Mitsui,' and 'retail = Yamada HD, Tsuruha.'