Comparison between degrees of polarization of IR sources in Mon R2, showing data from five polarimetric studies displayed based on date of collection: our study (collected in 2005), Yao et al. (1997) (collected in 1994), Aspin & Walther (1990) (collected in 1988), Hodapp (1987) (collected in 1983–1985, plotted for 1983). Filled circle: K- or K_s-band polarization data. Triangle: H-band polarization data.