[R-SIG-Finance] issue with xts affectin Return.calculate in PerformanceAnalytics

[susan22 at mail.com]

I came across the issue below trying to calculate simple returns of an xts object using Return.calculate() in PerformanceAnalytics. This returns a series of all zeros. The root of the problem, however, seems to be with xts for which division seems to be a challenge. What am I missing? Coercion to numeric is not really a reasonable solution.

> p <- to.monthly(as.xts(s.ts), OHLC = FALSE)
> head(aap)
                   s1           s2
Dec 1999      1000.00      1000.00
Jan 2000      1021.27       959.85
Feb 2000      1017.30       962.06
Mar 2000      1022.99      1008.44
Apr 2000      1015.95       980.95
May 2000      1044.30       963.79

> r <- Return.calculate(aap, method = "simple")
> head(r)
                   s1           s2
Dec 1999            0            0
Jan 2000            0            0
Feb 2000            0            0
Mar 2000            0            0
Apr 2000            0            0
May 2000            0            0

> lr <- Return.calculate(aap, method = "compound")
> head(lr)
                        s1                s2
Dec 1999                NA                NA
Jan 2000  0.02104695084364 -0.04097825672856
Feb 2000 -0.00389489202608  0.00229979652957
Mar 2000  0.00557765293308  0.04708304254280
Apr 2000 -0.00690557640376 -0.02763837145911
May 2000  0.02752266915648 -0.01764806131103

> p[2]/p[1]-1
Data:
numeric(0)

Index:
NULL

> as.numeric(p[2])/as.numeric(p[1])-1
[1]  0.02127 -0.04015