gvisMotionChart blank when animated - r

Question

Problem:
My gvisMotionChart works fine when paused, but is blank when animated.
Code:
Motion=gvisMotionChart(mydat,
idvar="Time_Period_Year_Cd",
timevar="Year",
xvar="Total_Customers",
yvar="Percent_Happy",
colorvar = "New_Product_Count",
sizevar = "Group_A_Count"
)
plot(Motion)
Result (when paused):
Result (when animated):
I imagine it must be something with my code or data, because I was able to get the example in the documentation to work properly. I tried several variations, like not specifying the xvar then plotting "year" as the x-axis, etc.
Data:
mydat <- structure(list(Time_Period_Year_Cd = c(201220L, 201320L, 201340L,
201360L, 201420L, 201440L, 201460L, 201480L, 201520L, 201540L,
201560L, 201580L, 201620L, 201640L, 201660L, 201680L, 201720L
), New_Product_Count = c(1606L, 1834L, 1205L, 1204L, 1645L, 704L,
651L, 473L, 692L, 559L, 535L, 531L, 911L, 663L, 599L, 702L, 512L
), Group_A_Count = c(616, 670, 512, 520, 594, 265, 215, 148,
235, 171, 160, 166, 231, 220, 148, 138, 101), Group_B_Count = c(267,
288, 177, 194, 320, 122, 156, 103, 121, 108, 105, 105, 187, 146,
134, 152, 103), Group_C_Count = c(365, 420, 293, 269, 373, 172,
151, 120, 192, 132, 135, 148, 225, 150, 191, 205, 177), Group_D_Count = c(333,
429, 202, 204, 335, 132, 121, 97, 133, 143, 131, 107, 264, 139,
119, 196, 129), Number_Bought_Per_Customer = c(5.46637608966376,
6.4432933478735, 6.79668049792531, 7.04734219269103, 7.2468085106383,
7.41193181818182, 7.44086021505376, 6.48625792811839, 6.91329479768786,
7.16994633273703, 6.49906542056075, 5.30885122410546, 4.78155872667398,
4.09049773755656, 3.80801335559265, 3.04415954415954, 2.826171875
), Total_Customers = c(5038L, 5940L, 5557L, 5472L, 6052L, 5164L,
4544L, 3954L, 4473L, 4948L, 3884L, 3723L, 4011L, 4303L, 3413L,
3421L, 2964L), Percent_Happy = c(0.797988105101756, 0.83794901700776,
0.773512106024391, 0.775157532067893, 0.834237370911927, 0.8306291015089,
0.820150552373225, 0.824696031621165, 0.776615269241095, 0.848073917652629,
0.841092657179119, 0.781823675677749, 0.840457049668049, 0.763698900181159,
0.872781703430453, 0.896473511416122, 0.787873482140602), Year = c(2012,
2013, 2013, 2013, 2014, 2014, 2014, 2014, 2015, 2015, 2015, 2015,
2016, 2016, 2016, 2016, 2017)), .Names = c("Time_Period_Year_Cd",
"New_Product_Count", "Group_A_Count", "Group_B_Count", "Group_C_Count",
"Group_D_Count", "Number_Bought_Per_Customer", "Total_Customers",
"Percent_Happy", "Year"), row.names = c(NA, 17L), class = "data.frame")

Answer 1

Each idvar value has only one timevar value:
mydat %>% count(Time_Period_Year_Cd) %>% head
# Time_Period_Year_Cd n
# <int> <int>
# 1 201220 1
# 2 201320 1
# 3 201340 1
# 4 201360 1
# 5 201420 1
# 6 201440 1
So there cannot be any transition. In contrast to e.g.
df <- mydat %>% mutate(idvar = substr(Time_Period_Year_Cd, 1, 4)) %>% group_by(idvar) %>% mutate(timevar = 1:n()) %>% ungroup
Motion=gvisMotionChart(df,
idvar="idvar",
timevar="timevar",
xvar="Total_Customers",
yvar="Percent_Happy",
colorvar = "New_Product_Count",
sizevar = "Group_A_Count"
)
plot(Motion)