Fig. 4
City-level energy efficiency in China obtained using DEA. (a) The energy efficiency in 2003, (b) the energy efficiency in 2007, (c) the energy efficiency in 2012, (d) the energy efficiency in 2016.
Fig. 4 | Scientific Data
City-level energy efficiency in China obtained using DEA. (a) The energy efficiency in 2003, (b) the energy efficiency in 2007, (c) the energy efficiency in 2012, (d) the energy efficiency in 2016.
