1/1/11 12/31/11 12/31/12 Intertech $2,500 $3,500 $4,375 Data Move $1,000 $1,200 $1,300 Biofix $2,100 $2,310 $2,079 Portfolio Value $5,600 $7,010 $7,754 Refer to Portfolio. What was the two-year holding period return for the portfolio in 2011? Assume any dividend payments are included in the market value shown above